Dopamine agonists for the treatment of pituitary tumours: From ergot extracts to next generation therapies.

Dopamine agonists are a key tool in the therapeutic arsenal of endocrinologists worldwide. They exert their effects by binding to dopamine-2 (D2) receptors expressed by pituitary tumour cells to modulate hormonal secretion and tumour size. They are the established first-line treatment for prolactinomas which express high levels of D2 receptors. Growing data support their use as an adjuvant treatment option for other pituitary tumours including growth hormone, adrenocorticotrophic hormones, thyroid hormone secreting adenomas and nonfunctional pituitary tumours, all of which have been shown to express D2 receptors as well, albeit to varying extents. For those pituitary tumours inadequately treated by dopamine agonist alone, combined agonism of D2 and somatostatin receptors represent a new frontier in clinical development. Here we review the development and role of dopamine agonist for the treatment of prolactinomas, the literature supporting their adjuvant use for the treatment of all other pituitary tumours, and recent progress in the development of the next generation of chimeric compounds that target D2 and other receptor subtypes highly expressed on pituitary tumour cells.

Effects of Quadruple Therapy Combined with Probiotics on Helicobacter Pylori-Related Peptic Ulcer.

The present study was designed to observe the effect of quadruple therapy combined with probiotics on Helicobacter pylori-related peptic ulcer. The patients in the control group (n = 90) were given regular quadruple therapy including proton pump inhibitor ilaprazole enteric-coated tablet + two antibiotics amoxicillin dispersible tablet and metronidazole tablet + colloidal bismuth pectin capsule for 2 weeks. Patients in the study group (n = 90) were given abovementioned quadruple therapy combined with probiotics live combined Bifidobacterium, Lactobacillus, and Enterococcus Capsules, oral for 2 weeks. Then Hp clearance rate, recurrence rate, levels of gastrointestinal hormone makers, and advance reactions between two groups were compared. At the 2nd week after the treatment, the Helicobacter pylori clearance rate in the study group (87.79%) was significantly higher than the control group (78.89%), and the total recurrence rate in the study group (6.67%) was significantly lower than the control group (13.33%) (P < 0.05). Serum gastrin and motilin expression were lower, and somatostatin expressions was significantly higher than those in the control group (P < 0.05). There was no significant difference in the total incidence of adverse reactions between the two groups (P > 0.05). In summary, quadruple therapy combined with probiotics in the treatment of Helicobacter pylori-related peptic ulcer can improve the Helicobacter pylori clearance rate, reduce the Helicobacter pylori recurrence rate, and is beneficial to improving the level of gastrointestinal hormones, with certain safety.

A Randomized Trial Evaluating Patient Experience and Preference Between Octreotide Long-Acting Release and Lanreotide for Treatment of Well-Differentiated Neuroendocrine Tumors.

PURPOSE: Somatostatin analogs octreotide long-acting release (octLAR) and lanreotide are equally acceptable in National Comprehensive Cancer Network guidelines for neuroendocrine tumors (NETs). Lanreotide is more expensive and given by deep subcutaneous injection, whereas octLAR is given intramuscularly. We evaluated patient preference between these agents in terms of injection site pain. MATERIALS AND METHODS: Randomized, single-blinded study. Patients with NETs received injections every 4 weeks. Arm 1: octLAR × 3, then lanreotide × 3; arm 2: reverse order. Self-reported injection site pain scores (range, 0-10) were obtained after each of the first three injections. Primary end point was comparison of mean pain scores over the first three injections. Secondary end points included patient-reported preference. RESULTS: Fifty-one patients enrolled (26 in arm 1 and 25 arm 2), all evaluable for primary end point. No significant difference was identified in the mean pain score over the first three injections (2.4 ± 1.9 v 1.9 ± 1.5, P = .5). Thirty-four of 51 (67%) patients (15 in arm 1 and 19 in arm 2) completed post-therapy questionnaires and were evaluable for secondary end points. Seven patients (47%) in arm 1 and eight patients (42%) in arm 2 indicated no drug preference at the end of treatment. In the other 19 patients, more patients indicated mild or strong preference for octLAR over lanreotide. CONCLUSION: We found minimal pain with octLAR and lanreotide and no significant pain score differences between the two. Patients indicating a drug preference trended toward favoring octLAR.

Unconventional treatment options in psoriasis: A review.

Psoriasis is a common skin disease that affects 1-3% of the general population. The treatment depends on body surface area involved, quality of life impairment and associated comorbidities. The treatment options include topical therapy, phototherapy, conventional systemic therapy (methotrexate, cyclosporine and acitretin), biologics and oral small molecules (apremilast and tofacitinib). Despite the availability of newer therapies such as biologics and oral small molecules, many a time, there is a paucity of treatment options due to the chronic nature of the disease, end-organ toxicity of the conventional drugs or high cost of newer drugs. In these scenarios, unconventional treatment options may be utilized as stand-alone or adjuvant therapy. In this review, we have discussed these uncommonly used treatment options in the management of psoriasis.

Cluster headache: state of the art of pharmacological treatments and therapeutic perspectives.

Cluster headache (CH) is the most common form of trigeminal autonomic cephalalgia. Current treatments have several limitations, and new drugs are required. This article first briefly reviews present acute and preventive treatments in CH, their mechanism of action and limitations, then describes the state of the art in recent clinical drug trials since 2015, and ends with a critique of trials in the CH field. Research is limited by lack of knowledge of pathophysiology and lack of animal models. In the past 5 years, no brand-new treatment has emerged, but promising drugs, such as CGRP(R) antibodies, are under study. According to the literature and guidelines, clinicians and researchers should be aware of many limitations in study protocols: concomitant medication, patient sample size, patients' protocol compliance, and study designs that tend to restrict patient recruitment.

Cost-effectiveness analysis of second-line pharmacological treatment of acromegaly in Spain.

Objective: To estimate the cost-effectiveness of second-line pharmacological treatments in patients with acromegaly resistant to first-generation somatostatin analogues (FG SSA) from the Spanish National Health System (NHS) perspective.Methods: A Markov model was developed to analyze the cost-effectiveness of pegvisomant and pasireotide in FG SSA-resistant acromegaly, simulating a cohort of patients from the treatment beginning to death. Treatment with pegvisomant or pasireotide was compared to FG SSA retreatment. Efficacy data were obtained from clinical trials and utilities from the literature. Direct health costs were obtained from Spanish sources (€2018).Results: The Incremental Cost Effectiveness Ratio (ICER) of pegvisomant vs. FG SSA was €85,869/Quality-adjusted life years (QALY). The ICER of pasireotide vs. FG SSA was €551,405/QALY. The ICER was mainly driven by the incremental efficacy (4.41 QALY for pegvisomant vs. FG SSA and 0.71 QALY for pasireotide vs. FG SSA), with a slightly lower increase in costs with pegvisomant (€378,597 vs. FG SSA) than with pasireotide (€393,151 vs. FG SSA).Conclusion: The ICER of pasireotide compared to FG SSA was six times higher than the ICER of pegvisomant vs. FG SSA. Pegvisomant is a more cost-effective alternative for the treatment of acromegaly in FG SSA-resistant patients in the Spanish NHS.

Postprandial hypoglycaemia after Roux-en-Y gastric bypass and the effects of acarbose, sitagliptin, verapamil, liraglutide and pasireotide.

AIM: To investigate the effects of acarbose, sitagliptin, verapamil, liraglutide and pasireotide on post-bariatric hypoglycaemia (PBH) after Roux-en-Y gastric bypass. MATERIALS AND METHODS: In a randomized crossover study, 11 women who had undergone Roux-en-Y gastric bypass and had documented hypoglycaemia were each evaluated during a baseline period without treatment and during five treatment periods with the following interventions: acarbose 50 mg for 1 week, sitagliptin 100 mg for 1 week, verapamil 120 mg for 1 week, liraglutide 1.2 mg for 3 weeks and pasireotide 300 µg as a single dose. Treatment effects were evaluated by a mixed-meal tolerance test (MMTT) and, for all treatment periods except pasireotide, by 6 days of continuous glucose monitoring (CGM). RESULTS: Treatment with acarbose and treatment with pasireotide both significantly lifted nadir glucose levels (mean ± SEM 3.9 ± 0.2 and 7.9 ± 0.4 vs 3.4 ± 0.2; P < .03) and reduced time in hypoglycaemia during the MMTTs. Acarbose reduced peak glucose levels and time in hyperglycaemia, whereas pasireotide greatly increased both variables. Acarbose and pasireotide reduced insulin and C-peptide levels, and pasireotide also diminished glucagon-like peptide-1 levels. Sitagliptin lowered nadir glucose values, while verapamil and liraglutide had no effect on hypoglycaemia. During the CGM periods, the treatments had no impact on hypoglycaemia, whereas acarbose and liraglutide reduced hyperglycaemia and glycaemic variability. CONCLUSIONS: In an experimental setting, treatment with acarbose and pasireotide reduced PBH. Acarbose appears to have an overall glucose-stabilizing effect, whereas pasireotide leads to increased and sustained hyperglycaemia.

Surgical-pharmacological interactions in the treatment of acromegaly.

INTRODUCTION: Acromegaly requires a multimodal treatment approach that includes surgery by an expert pituitary neurosurgeon, pharmacological treatment with one or more of the available drugs and radiation therapy. These treatment alternatives are not mutually exclusive but rather complement each other when properly indicated in the individual patient. In this review, we summarize and analyze the available data concerning the choice of the surgical approach (microscopy vs. endoscopy) and the interactions between medical treatment with somatostatin analogs and pituitary surgery. AREAS COVERED: Technical aspects, complications and outcome of transsphenoidal surgery (TSS); Advantages and disadvantages of the microscopic and endoscopic approaches; Safety and efficacy of somatostatin analogs (SSA); Primary pharmacological therapy versus primary TSS; Benefits of the preoperative treatment with SSA; and the effect of surgical tumor debulking in the therapeutic response to SSA. EXPERT COMMENTARY: Continuing efforts at improving surgical techniques and at generating more efficacious pharmacological therapies for acromegaly are likely to improve the outcome of these patients. However, an integral approach of the patient aimed not only at achieving biochemical criteria of cure but also at treating the individual comorbidities is mandatory to improve the quality of life of these patients and to reduce their mortality rate.

Pasireotide: A potential therapeutic alternative for resistant prolactinoma.

CONTEXT: About 10% of prolactinomas are resistant to dopamine-agonists (DAs). The only alternatives for tumor and prolactin control are surgery or radiotherapy. While studies on first generation somatostatin analogs have shown no efficacy against prolactinomas, no study has been conducted on the new multireceptor-targeted somatostatin receptor ligand pasireotide, which presents high affinity for 5, 3, 2 and 1 receptor subtypes. CASE DESCRIPTION: A 41 year-old woman presented with a macroprolactinoma showing resistance to all available DAs. She was first diagnosed at 17 years old after which she had undergone two incomplete debulking surgeries. Under pasireotide long-acting release (LAR) treatment, plasma prolactin levels normalized and symptoms disappeared within one month after initiation. The clinical benefits of the monotherapy (specifically, prolactin levels within normal range and stable tumor volume) were maintained for seven years. Glucose tolerance was satisfactory. Pathological analysis of the tumor revealed high SSTR5 and low SSTR2 expression (25 and 5% of cells respectively). CONCLUSION: This is a promising first report of a patient with a DA-resistant macroprolactinoma who achieved long-term control, in terms of prolactin normalization and tumor volume, under pasireotide treatment alone. Pasireotide could thus be an alternative in prolactinomas resistant to DA. SSTR expression analysis on pathology could guide patient selection.

Successful treatment of repeated hematemesis secondary to postsclerotherapy esophageal ulcer in a cirrhotic patient: A case report.

Esophageal variceal bleeding is a common lethal complication of cirrhosis. Endoscopic injection sclerotherapy (EIS) is one of the major endoscopic approaches for treating esophageal variceal bleeding. However, complications may occur after EIS, which mainly include retrosternal discomfort/pain, dysphagia, re-bleeding, esophageal ulcer, esophageal strictures, and esophageal perforation, etc. In this article, we reported a 36-year-old male who developed esophageal ulcer related bleeding after EIS. Currently, there is no consensus on the treatment strategy for esophageal ulcer-related bleeding after EIS. In the present case, the following treatment strategy may be effective for ulcer related bleeding. The first step is to inhibit gastric acid secretion and reduce portal pressure by intravenous infusion of esomeprazole and somatostatin, respectively. The second is local hemostasis by oral norepinephrine and lyophilizing thrombin powder. The third is to protect digestive tract mucosa by oral Kangfuxin Ye and aluminum phosphate.

Everolimus halts hepatic cystogenesis in a rodent model of polycystic-liver-disease.

AIM: To develop a MRI-based method for accurate determination of liver volume (LV) and to explore the effect of long-term everolimus (EVR) treatment on LV in PCK rats with hepatomegaly. METHODS: Thirty-one female PCK rats (model for polycystic-liver-disease: PCLD) were randomized into 3 groups and treatment was started at 16 wk, at the moment of extensive hepatomegaly (comparable to what is done in the human disease). Animals received: controls (n = 14), lanreotide (LAN: 3 mg/kg per 2 wk) (n = 10) or everolimus (EVR: 1 mg/kg per day) (n = 7). LV was measured at week 16, 24, 28. At week 28, all rats were sacrificed and liver tissue was harvested. Fibrosis was evaluated using quantitative image analysis. In addition, gene (quantitative RT-PCR) and protein expression (by Western blot) of the PI3K/AkT/mTOR signaling pathway was investigated. RESULTS: LV determination by MRI correlated excellent with the ex vivo measurements (r = 0.99, P < 0.001). The relative changes in LV at the end of treatment were: (controls) +31.8%; (LAN) +5.1% and (EVR) +8.8%, indicating a significantly halt of LV progression compared with controls (respectively, P = 0.01 and P = 0.04). Furthermore, EVR significantly reduced the amount of liver fibrosis (P = 0.004) thus might also prevent the development of portal hypertension. There was no difference in phosphorylation of Akt (Threonine 308) between LAN-treated PCK rats control PCK rats, whereas S6 was significantly more phosphorylated in the LAN group. Phosphorylation of Akt was not different between controls and EVR treated rats, however, for S6 there was significantly less phosphorylation in the EVR treated rats. Thus, both drugs interact with the PI3K/AkT/mTOR signaling cascade but acting at different molecular levels. CONCLUSION: Everolimus halts cyst growth comparable to lanreotide and reduces the development of fibrosis. mTOR-inhibition should be further explored in PCLD patients especially those that need immunosuppression.

TGR5 contributes to hepatic cystogenesis in rodents with polycystic liver diseases through cyclic adenosine monophosphate/Gαs signaling.

Hepatic cystogenesis in polycystic liver disease is associated with increased levels of cyclic adenosine monophosphate (cAMP) in cholangiocytes lining liver cysts. Takeda G protein receptor 5 (TGR5), a G protein-coupled bile acid receptor, is linked to cAMP and expressed in cholangiocytes. Therefore, we hypothesized that TGR5 might contribute to disease progression. We examined expression of TGR5 and Gα proteins in cultured cholangiocytes and in livers of animal models and humans with polycystic liver disease. In vitro, we assessed cholangiocyte proliferation, cAMP levels, and cyst growth in response to (1) TGR5 agonists (taurolithocholic acid, oleanolic acid [OA], and two synthetic compounds), (2) a novel TGR5 antagonist (m-tolyl 5-chloro-2-[ethylsulfonyl] pyrimidine-4-carboxylate [SBI-115]), and (3) a combination of SBI-115 and pasireotide, a somatostatin receptor analogue. In vivo, we examined hepatic cystogenesis in OA-treated polycystic kidney rats and after genetic elimination of TGR5 in double mutant TGR5-/- ;Pkhd1del2/del2 mice. Compared to control, expression of TGR5 and Gαs (but not Gαi and Gαq ) proteins was increased 2-fold to 3-fold in cystic cholangiocytes in vitro and in vivo. In vitro, TGR5 stimulation enhanced cAMP production, cell proliferation, and cyst growth by ∼40%; these effects were abolished after TGR5 reduction by short hairpin RNA. OA increased cystogenesis in polycystic kidney rats by 35%; in contrast, hepatic cystic areas were decreased by 45% in TGR5-deficient TGR5-/- ;Pkhd1del2/del2 mice. TGR5 expression and its colocalization with Gαs were increased ∼2-fold upon OA treatment. Levels of cAMP, cell proliferation, and cyst growth in vitro were decreased by ∼30% in cystic cholangiocytes after treatment with SBI-115 alone and by ∼50% when SBI-115 was combined with pasireotide. CONCLUSION: TGR5 contributes to hepatic cystogenesis by increasing cAMP and enhancing cholangiocyte proliferation; our data suggest that a TGR5 antagonist alone or concurrently with somatostatin receptor agonists represents a potential therapeutic approach in polycystic liver disease. (Hepatology 2017;66:1197-1218).

Add-on effect of crude rhubarb to somatostatin for acute pancreatitis: A meta-analysis of randomized controlled trials.

ETHNOPHARMACOLOGICAL RELEVANCE: Rhubarb is one of the common herbs used in traditional Chinese complex prescriptions for the treatment of various inflammatory diseases. We sought to determine the add-on effect of crude rhubarb to somatostatin in patients with acute pancreatitis by conducting a meta-analysis. MATERIALS AND METHODS: We searched the Pubmed, EMBASE, Cochrane Library, CNKI, Wanfang, VIP databases up to November 2015. Randomized controlled trials (RCTs) comparing crude rhubarb plus somatostatin to somatostatin alone for acute pancreatitis were included. Risk ratio (RR) or weighted mean difference (WMD) with their 95% confidence interval (CI) was calculated between with and without crude rhubarb therapy. RESULTS: A total of 19 RCTs involving 1161 patients were identified. Compared with somatostatin alone, crude rhubarb plus somatostatin significantly reduced the total complications (RR 0.55; 95% CI 0.41-0.73) and APACHE Ⅱ scores (WMD -1.16; 95% CI -1.91 to -0.41) as well as shortened the duration of elevated serum amylase (WMD -2.01 days; 95% CI -2.57 to -1.44), duration of abdominal pain (WMD -1.33 days; 95% CI -1.61 to -1.05), the first defecation time (WMD -2.27 days; 95% CI -3.06 to -1.47), and duration of hospital stay (WMD -6.70 days; 95% CI -8.81 to -4.60). However, there were no significant differences in total mortality rates (RR 0.61; 95% CI 0.34 to 1.12) between two groups. CONCLUSIONS: Crude rhubarb as adjuvant therapy to somatostatin appears to have additional benefits in patients with acute pancreatitis. However, interpretation of these results should be cautioned due to the methodological flaws.

New concepts in the treatment strategy of neuroendocrine tumors: the role of biotherapy.

Neuroendocrine tumors (NETs) comprise a wide range of neoplasms with diverse biological behaviors, often secreting excessive amounts of endocrine-active substances causing hormone syndromes. They are classified according to the location of the primary site and the level of histological differentiation, which has prognostic as well as therapeutic implications. Biotherapy had traditionally a significant role in the treatment of these tumors, when not amenable to surgery or local treatments. Control of carcinoid syndrome with somatostatin analogs (SSAs) significantly contributed to the improvement of the quality of life. Also, interferon has long been administered, but data were based on small studies. In contrast, PROMID and CLARINET randomized phase III trials provided the first strong evidence of significant improvement in progression-free survival in patients with gastroenteropancreatic (GEP)-NETs with octreotide and lanreotide, respectively, validating somatostatin receptors as important targets. Clinical trials testing the role of these SSAs in other primaries, e.g., lung carcinoids, as well as the efficacy of newer analogs are underway.

Medical Management of Meningiomas: Current Status, Failed Treatments, and Promising Horizons.

Meningiomas are benign tumors of the central nervous system, with low recurrence risk for World Health Organization (WHO) grade I lesions but a high risk for WHO grade II and III lesions. Current standard treatments include maximum safe surgical resection when indicated and radiation. Only three systemic therapies alpha-interferon, somatostatin receptor agonists, and vascular endothelial growth factor inhibitors are currently recommended by the National Comprehensive Cancer Network for treatment of recurrent meningioma. This paper aims to review medical approaches in the treatment of meningiomas.

Octreotide and Lanreotide in Gastroenteropancreatic Neuroendocrine Tumors.

Neuroendocrine tumors are heterogeneous, rare malignancies that arise most commonly in the gastrointestinal tract and pancreas. They often secrete vasoactive substances resulting in carcinoid syndrome and the tumor cells exclusively express somatostatin receptors. Octreotide and lanreotide are the two synthetic somatostatin analogs used for the control of carcinoid symptoms and tumor progression in advanced inoperable disease. Recent pivotal trials (PROMID and CLARINET studies) established their antitumor activity. We discuss the available data to support their use as symptom controlling and antiproliferative agents. This article also reviews the guidelines (National Comprehensive Cancer Network and North American Neuro Endocrine Tumor Society), cost-analysis (suggesting the cost-effectiveness of lanreotide autogel compared to higher doses of octreotide long acting release formulation in refractory patients), and future directions of somatostatin analogs in the management of patients refractory to conventional doses of octreotide and lanreotide.

Clinical management of critically ill patients with Cushing's disease due to ACTH-secreting pituitary macroadenomas: effectiveness of presurgical treatment with pasireotide.

The management of critically ill Cushing's disease (CD) patients is extremely challenging. Pasireotide is indicated for the treatment of CD patients when pituitary surgery is unfeasible or has not been curative, but no data are available about the use of this drug as pre-operative treatment in critically ill patients. We report the effects of presurgical pasireotide therapy in CD patients in whom hypercortisolism caused life-threatening hypokalemia, alkalosis, and cardio-respiratory complications precluding surgical approach. Clinical, biochemical, and radiological data of two critically ill patients with ACTH-secreting pituitary macroadenoma, before and during first-line presurgical pasireotide treatment (600 µg s.c. bid). During the first 21 days of treatment, pasireotide therapy induced a rapid, partial decrease of plasma ACTH, serum cortisol, and urinary free cortisol levels, with the consequent normalization of serum potassium concentration and arterial blood gases parameters, in both the patients. They did not experience unmanageable side effects and underwent endoscopic transsphenoidal surgery after 4 weeks of effective treatment. Pre-operative MRI evaluation did not show pituitary tumor shrinkage. Surgical cure of CD was obtained in the first patient, while debulking allowed the pharmacological control of hypercortisolism in the second case. We suggest that pasireotide can induce a rapid improvement of clinical and metabolic conditions in critically ill CD patients in whom surgical approach is considered hazardous and need to be delayed.

Hormone and Receptor Candidates for Target and Biotherapy of Neuroendocrine Tumors.

Neuroendocrine tumors (NETs) produce various hormones and bioactive substances and are known to express a large variety of peptide hormone receptors. While these hormones and receptors play a role in the pathophysiology of this heterogeneous group of tumors, they also form an important target for treatment and diagnosis. One of the most well-known target receptors in NETs are somatostatin receptors. On the basis of the expression of functional somatostatin receptors on the cell surface of NET cells, somatostatin analogs have already been used for decades to control symptoms related to hormonal overproduction in patients with NETs. Recent placebo-controlled studies have also demonstrated a significant antitumor activity, both in functioning and nonfunctioning NETs. Moreover, other peptide hormone receptors (e.g. receptors for GLP-1, CCK, GRP, secretin and dopamine) can be expressed at a high density in NETs. As such, these classes of receptors may also form potential targets for diagnosis and treatment. Finally, in recent years novel biotherapies targeting several growth factor systems have been introduced in the treatment of patients with NETs and are being explored for their efficacy in this setting, either as monotherapy or in combination treatment. This chapter aims to give an overview on the above topic.

Not So Giants: Mice Lacking Both Somatostatin and Cortistatin Have High GH Levels but Show No Changes in Growth Rate or IGF-1 Levels.

Somatostatin (SST) and cortistatin (CORT) are two highly related neuropeptides involved in the regulation of various endocrine secretions. In particular, SST and CORT are two primary negative regulators of GH secretion. Consequently, single SST or CORT knockout mice exhibit elevated GH levels; however, this does not lead to increased IGF-1 levels or somatic growth. This apparent lack of correspondence has been suggested to result from compensatory mechanisms between both peptides. To test this hypothesis, in this study we explored, for the first time, the consequences of simultaneously deleting endogenous SST and CORT by generating a double SST/CORT knockout mouse model and exploring its endocrine and metabolic phenotype. Our results demonstrate that simultaneous deletion of SST and CORT induced a drastic elevation of endogenous GH levels, which, surprisingly, did not lead to changes in growth rate or IGF-1 levels, suggesting the existence of additional factors/systems that, in the absence of endogenous SST and CORT, could counteract GH actions. Notably, elevation in circulating GH levels were not accompanied by changes in pituitary GH expression or by alterations in the expression of its main regulators (GHRH and ghrelin) or their receptors (GHRH receptor, GHS receptor, or SST/CORT receptors) at the hypothalamic or pituitary level. However, although double-SST/CORT knockout male mice exhibited normal glucose and insulin levels, they had improved insulin sensitivity compared with the control mice. Therefore, these results suggest the existence of an intricate interplay among the known (SST/CORT), and likely unknown, inhibitory components of the GH/IGF-1 axis to regulate somatic growth and glucose/insulin homeostasis.