Programming of the Hypothalamus-Pituitary-Adrenal Axis by Very Preterm Birth.

BACKGROUND: Many very preterm (i.e., <32 weeks of gestation) newborns fail to mount an adequate adrenocortical response to stress or illness, termed relative adrenal insufficiency. Conversely, later in life these infants show features of increased glucocorticoid bioactivity, such as abdominal adiposity, insulin resistance, raised blood pressure, shorter stature and internalizing problem behavior. SUMMARY: Studies suggested that very preterm newborns have impairments along multiple levels of the hypothalamus-pituitary-adrenal (HPA) axis. Among the impairment were defects in: (1) the pituitary responsiveness to exogenous corticotropin-releasing hormone, (2) 11ß-hydroxylase activity, and (3) the interconversion between cortisol and inert cortisone. There is some evidence suggesting that later in life these infants have an increased basal secretion rate of cortisol and adrenal hyperandrogenism. However, the response to acute (psychosocial) stress was blunted rather than enhanced in them. The mechanisms explaining this switch in HPA axis activity are complex and not yet fully understood. Key Messages: Very preterm newborns have several impairments along the HPA axis that could impede an adequate adrenocortical response to stress or illness. Later in life, these infants are predisposed to increased HPA axis activity, which could partially explain their phenotype.

Assessment of thyroid endocrine system impairment and oxidative stress mediated by cobalt ferrite (CoFe2 O4 ) nanoparticles in zebrafish larvae.

Fascinating super paramagnetic uniqueness of iron oxide particles at nano-scale level make them extremely useful in the state of the art therapies, equipments, and techniques. Cobalt ferrite (CoFe2 O4 ) magnetic nanoparticles (MNPs) are extensively used in nano-based medicine and electronics, results in extensive discharge and accumulation into the environment. However, very limited information is available for their endocrine disrupting potential in aquatic organisms. In this study, the thyroid endocrine disrupting ability of CoFe2 O4 NPs in Zebrafish larvae for 168-h post fertilization (hpf) was evaluated. The results showed the elevated amounts of T4 and T3 hormones by malformation of hypothalamus pituitary axis in zebrafish larvae. These elevated levels of whole body THs leads to delayed hatching, head and eye malformation, arrested development, and alterations in metabolism. The influence of THs disruption on ROS production and change in activities of catalase (CAT), mu-glutathione s-transferase (mu-GST), and acid phosphatase (AP) were also studied. The production of significantly higher amounts of in vivo generation of ROS leads to membrane damage and oxidative stress. Presences of NPs and NPs agglomerates/aggregates were also the contributing factors in mechanical damaging the membranes and physiological structure of thyroid axis. The increased activities of CAT, mu-GST, and AP confirmed the increased oxidative stress, possible DNA, and metabolic alterations, respectively. The excessive production of in vivo ROS leads to severe apoptosis in head, eye, and heart region confirming that malformation leads to malfunctioning of hypothalamus pituitary axis. ROS-induced oxidative DNA damage by formation of 8-OHdG DNA adducts elaborates the genotoxicity potential of CoFe2 O4 NPs. This study will help us to better understand the risk and assessment of endocrine disrupting potential of nanoparticles. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 2068-2080, 2016.

Neuroendocrine dysplasia in mice lacking protein tyrosine phosphatase sigma.

Protein tyrosine phosphatase sigma (PTP-sigma, encoded by the Ptprs gene) is a member of the LAR subfamily of receptor-like protein tyrosine phosphatases that is highly expressed during mammalian embryonic development in the germinal cell layer lining the lateral ventricles of the developing brain, dorsal root ganglia, Rathke's pouch, olfactory epithelium, retina and developing lung and heart. On the basis of its expression and homology with the Drosophila melanogasterorthologues DPTP99 and DPTP100A (refs 5,6), which have roles in the targeting of axonal growth cones, we hypothesized that PTP-sigma may also have a modulating function in cell-cell interactions, as well as in axon guidance during mammalian embryogenesis. To investigate its function in vivo, we generated Ptprs-deficient mice. The resulting Ptprs-/-animals display retarded growth, increased neonatal mortality, hyposmia and hypofecundity. Anatomical and histological analyses showed a decrease in overall brain size with a severe depletion of luteinizing hormone-releasing hormone (LHRH)-immunoreactive cells in Ptprs-/- hypothalamus. Ptprs-/- mice have an enlarged intermediate pituitary lobe, but smaller anterior and posterior lobes. These results suggest that tyrosine phosphorylation-dependent signalling pathways regulated by PTP-sigma influence the proliferation and/or adhesiveness of various cell types in the developing hypothalamo-pituitary axis.

[Biological mechanisms and genes involved in puberty]. / Mécanismes biologiques et gènes impliqués dans le développement de la puberté.

Puberty is an important step in human development. Onset of puberty, including neurobiological mechanisms important for the increase of hypothalamic GnRH pulses remains a mystery. After birth, GnRH secretion remains elevated and then decreases during childhood regardless of any steroid gonadal feedback. This period of quiescence of the gonadotropic axis during childhood is linked to a central inhibition of GnRH secretion which is replaced by an activator tone at puberty. The study of the pathology of the pubertal timing, including delayed puberty led to the discovery of new genes involved in the migration of GnRH neurons and genes involved in the neuroendocrine regulation of the gonadotropic axis. Recently, the emphasis on the importance of the kiss/GPR54 system in modulating control of the gonadotropic axis at puberty has recently emerged from Human genetics studies.

The environmental contaminant tributyltin leads to abnormalities in different levels of the hypothalamus-pituitary-thyroid axis in female rats.

Tributyltin is a biocide used in nautical paints, aiming to reduce fouling of barnacles in ships. Despite the fact that many effects of TBT on marine species are known, studies in mammals have been limited, especially those evaluating its effect on the function of the hypothalamus-pituitary-thyroid (HPT) axis. The aim of this study was to investigate the effects of subchronic exposure to TBT on the HPT axis in female rats. Female Wistar rats received vehicle, TBT 200 ng kg-1 BW d-1 or 1000 ng kg-1 BW d-1 orally by gavage for 40 d. Hypothalamus, pituitary, thyroid, liver and blood samples were collected. TBT200 and TBT1000 thyroids showed vacuolated follicular cells, with follicular hypertrophy and hyperplasia. An increase in epithelial height and a decrease in the thyroid follicle and colloid area were observed in TBT1000 rats. Moreover, an increase in the epithelium/colloid area ratio was observed in both TBT groups. Lower TRH mRNA expression was observed in the hypothalami of TBT200 and TBT1000 rats. An increase in Dio1 mRNA levels was observed in the hypothalamus and thyroid in TBT1000 rats only. TSH serum levels were increased in TBT200 rats. In TBT1000 rats, there was a decrease in total T4 serum levels compared to control rats, whereas T3 serum levels did not show significant alterations. We conclude that TBT exposure can promote critical abnormalities in the HPT axis, including changes in TRH mRNA expression and serum TSH and T4 levels, in addition to affecting thyroid morphology. These findings demonstrate that TBT disrupts the HPT axis. Additionally, the changes found in thyroid hormones suggest that TBT may interfere with the peripheral metabolism of these hormones, an idea corroborated by the observed changes in Dio1 mRNA levels. Therefore, TBT exposition might interfere not only with the thyroid axis but also with thyroid hormone metabolism.

Clinical Consultation Guide on Imaging in Male Infertility and Sexual dysfunction.

Imaging can benefit clinicians in evaluating men with infertility or sexual dysfunction by giving an overview of a patient's overall clinical condition before undertaking an invasive procedure. An understanding of the limitations and advantages of image modalities used in clinical practice will ensure that clinicians can optimize patient care with imaging when necessary. PATIENT SUMMARY: The objective of this article was to review the current literature on imaging modalities used for the diagnosis and management of male infertility and sexual dysfunction. An understanding of the advantages and limitations of these imaging modalities will ensure that clinicians can optimize patient care with imaging when necessary.

GH response to ghrelin in subjects with congenital GH deficiency: evidence that ghrelin action requires hypothalamic-pituitary connections.

OBJECTIVES: Evaluation of GH response to ghrelin in patients with GH deficiency (GHD) may help to elucidate the site and mechanism of action of ghrelin. We aimed to investigate the GH-releasing effect of ghrelin in children and young adults with childhood-onset GHD. DESIGN: All subjects underwent ghrelin testing and neuro-imaging examination. Magnetic resonance imaging evidenced the presence of a vascular pituitary stalk (VPS) or its complete absence (PSA). PATIENTS AND METHODS: Seventeen prepubertal children and nine adult patients with childhood-onset GHD were selected for the study. The children were enrolled at a median age of 5.8 years. The adult subjects were included at a median age of 23.3 years. The diagnosis of GHD in the adult patients had been established at a median age of 8.5 years. Ghrelin was administered at a dose of 1 microg/kg body weight, i.v. at time zero, and blood for GH determination was obtained at 0, 15, 30, 45, 60, 75, 90, 105 and 120 min. RESULTS: Median GH response after ghrelin was similar between children and adults. Median peak GH response to ghrelin (7.45 microg/l, IQR: 3.9-11.3 microg/l) was significantly higher in patients with VPS (10.9 microg/l, IQR: 2.4-15.1 mcirog/l) than in those with PSA (IQR: 2.3-6.7 microg/l; P=0.001). It was significantly higher in subjects with isolated GHD (12.5 microg/l, IQR: 10.8-15.5 microg/l) than in those with multiple pituitary hormone deficiencies (5.15 microg/l, IQR: 2.4-9.0 microg/l; P=0.003). No correlation was found between the GH peak after ghrelin and body mass index. CONCLUSION: The GH response to ghrelin in patients with congenital hypopituitarism depends on the degree of the anatomical abnormalities and lends further support to the assumption that the main action of the peptide is exerted at the hypothalamic level and requires the integrity of hypothalamic-pituitary connections.

Circadian pattern of prolactin secretion in children with growth hormone deficiency and congenital organic lesions in the hypothalamic-pituitary region.

OBJECTIVES: Prolactin (Prl) secretion in children manifests circadian rhythm. The aim of the study was to assess circadian Prl pattern in children with growth hormone deficiency (GHD) and congenital organic disorders in the hypothalamic-pituitary region (HPR). MATERIAL AND METHODS: The analysis comprised 47 children (aged: 11.05+/-3.5 years) with GHD, divided (based on MRI) into subgroups: NORM (no disturbances in HPR); HP (pituitary hypoplasia) and PSIS (pituitary stalk interruption syndrome). The profile of circadian Prl secretion was determined, based on Prl measurements in serum every 3 hours during 24 hours. The macroscopic analysis of circadian Prl rhythm in particular groups was performed. The comparison group consists of 41 children (aged: 11.45+/-3.20 years) with idiopathic short stature (ISS). RESULTS: In GHD-HP, diurnal and nocturnal Prl concentrations were low but with the dispersion between them and with normal rhythm in most of cases. In GHD-PSIS, diurnal and nocturnal Prl concentrations were on the same level and the rhythm was not observed in most of cases. No significant differences were found in Prl secretions and Prl rhythm between GHD-NORM and ISS. The rhythm of Prl secretion was disturbed in: 72.7% of children with GHD-PSIS, 23.5% - with GHD-HP, 10.5% with GHD-NORM and 7.3% with ISS, only. CONCLUSIONS: Congenital organic lesions of HPR are associated with quantitative disorders and changes of the circadian pattern of Prl secretion. In children with GHD without organic lesions of HPR, the circadian rhythm of Prl secretion was not different from that with ISS.

Final height and growth hormone secretion after completion of growth hormone therapy in patients with idiopathic growth hormone deficiency and with abnormalities of the hypothalamic-pituitary region.

AIMS: The aim of the study was an evaluation of final height and growth hormone (GH) secretion after completion of GH therapy (retesting) in patients with GH deficiency (GHD). PATIENTS AND METHODS: The analysis comprised 53 patients (43 boys, 10 girls) with childhood-onset GHD, who completed GH therapy and reached final height. Magnetic resonance imaging (MRI), performed in all the patients, led to the following groups: pituitary stalk interruption syndrome (PSIS), pituitary hypoplasia (HP), craniopharyngioma (CP) -- patients after tumour excision, patients with normal hypothalamic-pituitary region (NP). RESULTS: In 51 patients, final height was normal. The height gain was significantly (p<0.05) greater in PSIS than in that other groups. In retesting, GH secretion was significantly (p<0.005) lower in PSIS and CP than in HP and in NP and also (p<0.05) in HP than in NP. Permanent severe GHD was confirmed in all the patients with PSIS and CP and in some patients with HP (37.5%), while it was excluded in all the patients with normal pituitary in MRI. CONCLUSIONS: It seems that in patients with PSIS and CP, the confirmation of persistent character of GHD needs no retesting, while in patients with normal MRI results, GHD diagnosis should be established with special attention.

Childhood maltreatment increases the risk for visceral obesity.

OBJECTIVE: The reports regarding the associations between childhood maltreatment (CM) and body fat composition remain heterogeneous in humans although they are indicated in preclinical studies. In addition, the effects of CM subtypes on different types of body fat are unclear. Thus, in this study, the associations between CM and its subtypes with body fat were determined and the potential pathways were explored. METHODS: The participants were assessed for a history of CM by the Childhood Trauma Questionnaire and were divided into the CM group (with CM exposures) and non-CM group (without CM exposures). Body composition was measured by dual-energy X-ray absorptiometry. Salivary and blood samples were provided by the subjects. RESULTS: Compared with the non-CM group, subjects with a history of CM had greater visceral fat mass (1,136 ± 160 vs. 836 ± 116 g, P < 0.05) but not total body fat, android fat, body mass index, or waist-to-hip ratio. In addition, subjects with CM had a blunted cortisol awakening response and elevated inflammatory factors. Correlation analysis indicated that CM subtypes had differential effects on visceral adiposity and cortisol awakening response. CONCLUSIONS: It is suggested by our results that CM exposure is linked with increased visceral fat deposition, and the perturbation of the hypothalamic-pituitary-adrenal axis activity and activation of the immune system may be two potential pathways through which this relationship is explained.

NELF knockout is associated with impaired pubertal development and subfertility.

Puberty and reproduction require proper signaling of the hypothalamic-pituitary-gonadal axis controlled by gonadotropin-releasing hormone (GnRH) neurons, which arise in the olfactory placode region and migrate along olfactory axons to the hypothalamus. Factors adversely affecting GnRH neuron specification, migration, and function lead to delayed puberty and infertility. Nasal embryonic luteinizing hormone-releasing factor (NELF) is a predominantly nuclear protein. NELF mutations have been demonstrated in patients with hypogonadotropic hypogonadism, but biallelic mutations are rare and heterozygous NELF mutations typically co-exist with mutations in another gene. Our previous studies in immortalized GnRH neurons supported a role for NELF in GnRH neuron migration. To better understand the physiology of NELF, a homozygous Nelf knockout (KO) mouse model was generated. Our findings indicate that female Nelf KO mice have delayed vaginal opening but no delay in time to first estrus, decreased uterine weight, and reduced GnRH neuron number. In contrast, male mice were normal at puberty. Both sexes of mice had impaired fertility manifested as reduced mean litter size. These data support that NELF has important reproductive functions. The milder than expected phenotype of KO mice also recapitulates the human phenotype since heterozygous NELF mutations usually require an additional mutation in a second gene to result in hypogonadotropic hypogonadism.

Endocrine status in patients with optic nerve hypoplasia: relationship to midline central nervous system abnormalities and appearance of the hypothalamic-pituitary axis on magnetic resonance imaging.

We here: 1) describe the phenotypic spectrum, including magnetic resonance imaging (MRI) appearances of the pituitary stalk and anterior and posterior pituitary [H-P (hypothalamic-pituitary) axis], in children with optic nerve hypoplasia (ONH) with or without an abnormal septum pellucidum (SP); and 2) define endocrine dysfunction according to the MRI findings. Medical records of 55 children with ONH who had been assessed by ophthalmology and endocrine services were reviewed. All had MRI of the brain and H-P axis. Forty-nine percent of the ONH patients had an abnormal SP on MRI, and 64% had a H-P axis abnormality. Twenty-seven patients (49%) had endocrine dysfunction, and 23 of these had H-P axis abnormality. The frequency of endocrinopathy was higher in patients with an abnormal SP (56%) than a normal SP (39%). Patients were divided into four groups based on SP and H-P axis appearance: 1) both normal; 2) abnormal SP and normal H-P axis; 3) normal SP and abnormal H-P axis; and 4) both abnormal. The frequency of multiple pituitary hormone deficiency was highest (56%) in group 4, lower (35%) in group 3, and even lower (22%) in group 2. Precocious puberty was most common in group 2. None of the patients in group 1 had endocrine dysfunction. Thus, SP and H-P axis appearances on MRI can be used to predict the likely spectrum of endocrinopathy.

Ectrodactyly-ectodermal dysplasia-clefting syndrome and hypothalamo-pituitary insufficiency.

We report on 2 brothers with ectrodactyly-ectodermal dysplasia-clefting (EEC) syndrome and hypothalamo-pituitary insufficiency. Both had hypogonadotropic hypogonadism. One brother had partial TSH and prolactin deficiency, and the other had mild primary hypothyroidism, due most probably to irradiation therapy which he had undergone a few years earlier because of Hodgkin disease. The association of hypogonadotropic hypogonadism with EEC was reported once previously. Hypothalamopituitary dysfunction could be considered as yet another manifestation of EEC syndrome. This report reconfirms that EEC syndrome is a pleiotropic trait with reduced penetrance. Alternatively, we may be dealing with a (new) autosomal or X-linked recessive condition.

Hypothalamic-hypophyseal dysgenesis as a neuroimaging correlate of pituitary hormone deficiency in anophthalmia.

PURPOSE: To document the association of neurohypophyseal dysgenesis with hypopituitarism in a child with primary bilateral anophthalmia. METHODS: An infant with bilateral anophthalmia underwent magnetic resonance imaging and endocrinologic evaluation. RESULTS: Magnetic resonance imaging showed dysgenesis confined to the hypothalamus and hypophyseal stalk. Endocrinologic testing showed low serum cortisol and pituitary gonadotropin levels. CONCLUSION: Magnetic resonance imaging can help predict which children with anophthalmia will have endocrinologic deficiencies.

Idiopathic growth hormone deficiency: MR findings in 35 patients.

Idiopathic growth hormone deficiency is a disorder that is not clearly understood. We therefore evaluated the MR scans of 35 patients with idiopathic growth hormone deficiency in an attempt to define more clearly the abnormalities of the hypothalamohypophyseal axis, determine the frequency of these abnormalities, and determine whether a relationship exists between the MR findings and the patient's clinical history and endocrine function. Patients with MR abnormalities fell into two groups; those with an ectopic neurohypophysis (15 patients, or 43%), which consisted of a neurohypophysis near the median eminence, absence of the infundibulum, and absence of the normal posterior pituitary bright spot; and those with a small anterior pituitary gland (15 patients, or 43%), which was an isolated finding in five patients and associated with an ectopic neurohypophysis in 10 patients. Examination of endocrine function identified two groups of patients: those with multiple hormone deficiencies and those with isolated growth hormone deficiency. An ectopic neurohypophysis was present in 87% of the first group and 10% of the second group. The anterior pituitary dysfunction in those with an ectopic neurohypophysis was thought to be related to the absent infundibulum, which normally houses the portal system. Our MR findings demonstrated that over 40% of patients with idiopathic growth hormone deficiency have an ectopic neurohypophysis and absence of the infundibulum. We believe that the growth hormone deficiency in these patients is related to the absent infundibulum.

Syndrome of septo-optic-pituitary dysplasia: the clinical spectrum.

Septo-optic-pituitary dysplasia is a syndrome characterized by abnormalities of midline brain structures, optic nerve hypoplasia, and congenital hypothalamic-pituitary insufficiency. Four infants, diagnosed as having clinical variations of this disorder, are described. The first had agenesis of the septum pellucidum and corpus callosum, partial hypothalamic insufficiency, and normal optic nerves. The second had a structurally normal brain, bilateral optic nerve hypoplasia, and panhypopituitarism. The third had bilateral agenesis of the cerebral cortex, bilateral optic nerve hypoplasia and partial hypothalamic insufficiency. The fourth had a structurally normal brain, unilateral optic nerve hypoplasia and panhypopituitarism. A review of the recent literature revealed 191 patients with bilateral optic nerve hypoplasia who were examined for possible existence of this syndrome. Of the 178 patients who had radiographic imaging of the brain, 60% were found to have structural abnormalities. Of the 145 patients evaluated for pituitary function, 62% had evidence of insufficiency. Approximately 30% of fully evaluated patients had evidence of all three components of the syndrome. Because of high incidence of structural abnormalities of the brain and congenital hypopituitarism in patients with optic nerve hypoplasia, we conclude that full evaluation is indicated in patients with any of the three components of the syndrome.

Septo-optic dysplasia (case report).

Septo optic dysplasia is a rare developmental anomaly involving bilateral optic nerve hypoplasia, midline anomalies of the brain and hypothalamo-pituitary dysfunction. A case of septo-optic dysplasia with pituitary dwarfism, optic nerve hypoplasia and absent septum pellucidum is reported.

[Ante- and posthypophyseal insufficiency with infundibulum abnormalities]. / Insuffisance anté-et post-hypophysaire avec anomalies de la tige pituitaire.

The hypopituitarism and the diabetes insipidus are often idiopathic. A retrospective study of 6 cases of diabetes insipidus and 8 cases of partial or total idiopathic antehypophyseal insufficiency has shown the value of MRI to demonstrate anomalies of the infundibulum or hypothalamic-hypophysis "stages". MRI allows to bring together some cases of idiopathic hypopituitarism in a new entity which is the hypopituitarism due to a newborn section of the infundibulum.

[Neuroradiological investigation in patients with idiopathic growth hormone deficiency]. / Investigação neurorradiológica de pacientes com deficiência idiopática de hormônio do crescimento.

OBJECTIVE: The aim of this study was to analyze the type and frequency of cranial computed tomography and magnetic resonance imaging anomalies in patients with idiopathic growth hormone deficiency, and also to investigate the possible relationship between neuroradiological images and the presence of isolated growth hormone or multiple pituitary hormone deficiency. METHODS: Magnetic resonance and computed tomography images were obtained for 37 patients with idiopathic growth hormone deficiency. The patients were divided into two groups: patients with isolated growth hormone (group A) and patients with multiple pituitary hormone deficiencies (group B). RESULTS: Computed tomography was normal in 25 (68%), and abnormal in 12 (32%) patients. We observed empty sella in 50%, partially empty sella in 17% and anterior pituitary hypoplasia in 33% patients. MRI studies revealed normal findings in the hypothalamus-pituitary area in 17 (46%) and abnormal in 20 (54%) patients. We did not observed differences in the frequency of computed tomography alterations when groups A and B were compared (p = 0.55). With magnetic resonance imaging we observed, empty sella in 10%, partially empty sella in 15% and anterior pituitary hypoplasia in 75% patients. Among those patients whose magnetic resonance images were altered, the posterior lobe of the pituitary gland was identified in an abnormal position in 70%, and the hypophyseal stalk was thin or interrupted in 60%. The patients from group B presented a higher frequency of magnetic resonance imaging anomalies (90%) when compared to group A (10%), p = 0.03. There was disagreement between the two methods in 43% of cases, but we didn't observe a difference in the frequency of alterations when computed tomography was compared with magnetic resonance imaging (p = 0.06). CONCLUSIONS: The most frequent defects observed using magnetic resonance imaging are anterior pituitary hypoplasia and ectopic posterior pituitary lobe. The association of glandular hypoplasia with other magnetic resonance imaging abnormalities can suggest the presence of multiple anterior pituitary deficiencies.

[Diabetes insipidus with a hypothalamo-hypophyseal morphologic anomaly during a pregnancy]. / Diabète insipide avec anomalie morphologique hypothalamo-hypophysaire au cours d'une grossesse.

BACKGROUND: Diabetes insipidus is uncommon in pregnancy. Despite physiological modifications in hydroelectrolytic balance during normal pregnancy, the capacity of the kidney to concentrate urine is preserved, partially due to lower vasopressin secretion. CASE REPORT: A young woman developed diabetes insipidus during the third trimester of normal pregnancy. The disease regressed totally after delivery. However, magnetic resonance imaging revealed a persistent expansive intrasellar image with a high-intensity signal. DISCUSSION: Onset of diabetes insipidus is usually rapidly progressive in pregnancy. Occurring generally during the third trimester in normal pregnancies, diabetes insipidus is generally well tolerated and responds to dDAVP, usually without pituitary abnormally, and regresses after delivery. Two types are distinguished: partially latent diabetes insipidus occurring during pregnancy and due to a central rather than nephrogenic origin; and excessive vasopressinase activity leading to diabetes insipidus usually associated with liver anomalies and high frequency of pre-eclampsia. During normal pregnancy, the size of the anterior pituitary increases and the normal high-intensity signal in the posterior pituitary seen on MRI usually regresses or disappears. In diabetes insipidus, the posterior pituitary hypersignal image generally disappears, reflecting reduced vasopressin storage. Few observations of diabetes insipidus occurring during pregnancy have been reported with morphological explorations. Most have described a "normal" aspect of the pituitary, specifically in the post partum period. In our patient, the weak vasopressin response to the end of water restriction at post partum when the diabetes insipidus symptoms had disappeared would suggest partial central diabetes insipidus revealed by pregnancy. Other pathologies involving this region could also be involved due to the unusual and persistent sellar image, with an expansive process showing a high intensity signal on MRI. An asymptomatic craniopharyngioma cyst was hypothesized and would be more compatible with the observed symptoms.