RESUMO
Recent publicized events of cryogenic storage tank failures have created nationwide concern among infertility patients and patients storing embryos and gametes for future use. To assure patient confidence, quality management (QM) plans applied by in vitro fertilization (IVF) laboratories need to include a more comprehensive focus on the cryostorage of reproductive specimens. The purpose of this review is to provide best practice guidelines for the cryogenic storage of sperm, oocytes, embryos, and other reproductive tissues (e.g., testicular and ovarian tissue, cord blood cells, and stem cells) and recommend a strategy of thorough and appropriate quality and risk management procedures aimed to alleviate or minimize the consequences from catastrophic events.
Assuntos
Criopreservação/métodos , Guias de Prática Clínica como Assunto/normas , Garantia da Qualidade dos Cuidados de Saúde/normas , Técnicas de Reprodução Assistida/normas , Bancos de Tecidos/normas , HumanosRESUMO
Serotonin is thought to be intimately involved in the regulation of sleep and waking in humans, though the evidence for such is indirect. Using in vivo microdialysis, the authors show that serotonin in human ventricular CSF covaries with the state of consciousness. They hypothesize that CSF serotonin may be acting in an endocrine-like manner through activation of known leptomeningeal serotonin receptors and possibly participating in modulation of choroidal production of CSF.
Assuntos
Ciclos de Atividade/fisiologia , Ventrículos Laterais/metabolismo , Serotonina/líquido cefalorraquidiano , Sono REM/fisiologia , Adulto , Eletroencefalografia/estatística & dados numéricos , Humanos , MasculinoRESUMO
In this study we compared the position of the electronically active contact of the thalamic (Vim) deep brain stimulation (DBS) electrode to the stereotactic location of its tip. Fifteen patients with either Parkinson's disease (PD) or essential tremor (ET) underwent stereotactic, MRI-based placement of the Medtronic quadripolar DBS electrode. An overall improvement of 69% was achieved in the tremor scores during a period of 1-13 months after implantation of the DBS electrode. Eleven patients with ET showed 70% clinical improvement of tremor, compared to a 58% response observed in the 4 patients with PD. The electrode tip center was 11.2 +/- 1.54 mm lateral to the third ventricular wall, 5.38 +/- 1.02 mm anterior to the posterior commissure and 2.9 +/- 3.57 mm inferior to the level of AC-PC line. The most significant deviation from the planned stereotactic target was observed in the Z-coordinate. In our group of patients, stimulation settings favored the contacts closer to the AC-PC line, correcting the electrode tip position to 0.80 +/- 2.84 mm (p < 0.001) inferior to the level of the AC-PC line. In our experience, thalamic DBS offers a reversible and adjustable 'lesion' to compensate for the anatomic variabilities encountered in the positioning of the DBS electrode tip.
Assuntos
Mapeamento Encefálico/métodos , Terapia por Estimulação Elétrica/métodos , Eletrodos Implantados , Imageamento por Ressonância Magnética , Doença de Parkinson/terapia , Técnicas Estereotáxicas , Tremor/terapia , Núcleos Ventrais do Tálamo , Idoso , Terapia por Estimulação Elétrica/instrumentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desempenho Psicomotor , Técnicas Estereotáxicas/instrumentação , Resultado do Tratamento , Núcleos Ventrais do Tálamo/patologia , Núcleos Ventrais do Tálamo/fisiopatologiaRESUMO
Paired pulse stimulation has commonly been employed to investigate changes in excitability in epileptic hippocampal tissue employing the in vitro slice preparation. We used paired pulse stimulation in the intact temporal lobe of patients with temporal lobe seizures to compare the excitability of pathways in the epileptogenic hippocampus (located in the temporal lobe in which seizures arise) with those in the non-epileptogenic hippocampus of the contralateral temporal lobe (in the hemisphere to which seizures spread). A total of 20 patients with temporal lobe seizure onsets were studied during chronic depth electrode monitoring for seizure localization. Intracranial in vivo stimulation and recording sites included the hippocampus, entorhinal cortex, subicular cortex and parahippocampal gyrus. A comparison of all hippocampal pathways located in the temporal lobe where seizures typically started (n = 37) with those in temporal lobes contralateral to seizure onset (n = 53) showed significantly greater paired pulse suppression of population post-synaptic potentials on the epileptogenic side (F(1,87) = 6.1, P < 0.01). Similarly, mean paired pulse suppression was significantly greater for epileptogenic perforant path responses than for contralateral perforant path responses (F(1,13) = 7.5, P < 0.01). In contrast, local stimulation activating intrinsic associational pathways of the epileptogenic hippocampus showed decreased paired pulse suppression in comparison to the epileptogenic perforant path. These results may be a functional consequence of the formation of abnormal recurrent inhibitory and recurrent excitatory pathways in the sclerotic hippocampus. Enhanced inhibition may be adaptive in suppressing seizures during interictal periods, while abnormal recurrent excitatory circuits in the presence of enhanced inhibition may drive the hypersynchronization of principal neurons necessary for seizure genesis.
Assuntos
Epilepsia/fisiopatologia , Hipocampo/fisiopatologia , Potenciais de Ação/fisiologia , Adulto , Estimulação Elétrica , Eletrodos Implantados , Eletroencefalografia , Epilepsia/patologia , Feminino , Hipocampo/patologia , Humanos , Masculino , Vias Neurais/fisiologiaRESUMO
A 21-year-old multiparous female exhibiting 31-41 day menstrual cycles was given hFSH (225 IU/day, Metrodin 75, from cycle day 3 through 9 (menses = day 1) and hCG (10,000 IU, Profasi, on day 10 to stimulate follicular development. At 35 h after hCG, under isoflurane (AErrane) anesthesia, follicles were aspirated by controlled suction under transvaginal ultrasound guidance. Metaphase II oocytes (n = 11) were placed in modified human tubal fluid (mHTF, 100 microliters) medium under oil at 37 degrees C in humidified 5% CO2. Frozen semen, collected by voluntary ejaculation, was thawed (70 degrees C H2O bath, 6 sec), diluted slowly, centrifuged, and resuspended in mHTF, and 160,000 motile spermatozoa/ml were added at 6 h after oocyte recovery. At 21 h postinsemination (p.i.) eight oocytes were at the two-cell stage, five were cryopreserved, and three were cultured to the six- to eight-cell stage in mHTF with granulosa cells before transcervical uterine transfer at 47 h p.i. using a Teflon catheter. Micronized progesterone (400 mg/d) was orally administered for 10 weeks posttransfer (p.t.). Ultrasound examination revealed a single fetus at 15 weeks p.t., and unassisted delivery of a live 1.37 kg female infant occurred at 29 weeks. Am. J. Primatol. 41:247-260, 1997.
Assuntos
Transferência Embrionária/veterinária , Fertilização in vitro/veterinária , Gorilla gorilla , Animais , Criopreservação/veterinária , Transferência Embrionária/métodos , Feminino , Fertilização in vitro/métodos , Hormônio Foliculoestimulante/administração & dosagem , Ciclo Menstrual/fisiologia , Oócitos , Preservação do Sêmen/veterináriaRESUMO
Recent microdialysis studies of excitatory and inhibitory amino acid release associated with paroxysmal hippocampal activity have found significant increases in the hippocampus of epileptic patients, but minimal or variable increases in animal models. One possible reason for the difference is that the animal models employed in these studies have not adequately reflected the pathophysiology of human epilepsy. The present study sought to verify the amino acid release reported in human epileptic hippocampus and then employs animal studies using a chronic rat model of epilepsy, in which rats exhibit spontaneous seizure activity 3 to 4 months after injection of kainic acid into the hippocampus. In agreement with earlier reports, we found increases in glutamate, aspartate and GABA during seizures in human hippocampus. In addition we found increases in taurine which have not previously been reported. The chronic rat model shows increases in the same amino acids as in the human epileptic hippocampus, both during spontaneous seizures and stimulation evoked after-discharges (ADs). In contrast, minimal increases are elicited by hippocampal stimulation in control (non-kainate injected) animals. These results correlate with the degree of mossy fiber reorganization found in the dentate gyrus of kainate rats or epileptic humans.
Assuntos
Aminoácidos/metabolismo , Epilepsia/induzido quimicamente , Epilepsia/metabolismo , Hipocampo/metabolismo , Ácido Caínico , Animais , Eletroencefalografia , Epilepsia/fisiopatologia , Aminoácidos Excitatórios/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/fisiopatologia , Humanos , Ácido Caínico/farmacologia , Microdiálise , Ratos , Ratos Sprague-Dawley , Taurina/metabolismo , Ácido gama-Aminobutírico/metabolismoRESUMO
PURPOSE: Our purpose was to determine if the progesterone concentration on the day of HCG administration is associated with the establishment of pregnancy in IVF patients. METHODS: Concentrations of progesterone on the day of hCG were examined retrospectively in 293 patients with ovarian hyperstimulation induced by GnRH agonist with hMG and/or FSH. Patients were grouped based on progesterone concentration: < 0.9, 0.9 to < 1.2, 1.2 to < 1.5, and > or = 1.5 ng/ml. Oocytes recovered, fertilization rate, and pregnancy rate were compared among groups. RESULTS: Patients with a higher concentration of progesterone had increased concentrations of estradiol and greater numbers of oocytes retrieved. No differences were found for fertilization rate, polyploid fertilization, or pregnancy rate. It was noted that there was an association between the type of luteal support and the effect of high preovulatory progesterone on pregnancy rate. CONCLUSIONS: These data suggest that oocytes and embryos derived from patients with high preovulatory progesterone are not of a reduced quality. The association of high progesterone concentrations with a reduced rate of pregnancy varied with the type of luteal support.
Assuntos
Gonadotropina Coriônica/administração & dosagem , Estradiol/sangue , Fertilização in vitro , Indução da Ovulação , Progesterona/sangue , Biomarcadores/sangue , Feminino , Humanos , Estudos Retrospectivos , Fatores de TempoRESUMO
Eleven patients who underwent stereotactic radiofrequency lesions in the central nervous system had magnetic resonance imaging follow-up within 72 hours of surgery to determine the early appearance of their lesions. Eight patients with severe tremor, one with chronic pain, and two with dystonia were analyzed. There were six female patients and five male patients, age 7 to 75 years (mean +/- standard deviation = 42 +/- 21). Magnetic resonance imaging was performed postoperatively at 32 +/- 25 hours (range, 3-72). Postoperative T1-weighted spin echo images demonstrated foci of iso- to hyperintensity surrounded by an edge of hypointensity, and corresponding T2-weighted images showed a lesion with three concentric zones consisting of inner hypointense, middle hyperintense, and outer hypointense zones. Gadolinium increased T1-weighted image lesion visibility, and a ring of enhancement around the zone of hypointensity was observed. Lesions could be seen as early as 3 hours after surgery. The lesions were best shown on gadolinium-enhanced T1-weighted images and on T2-weighted images. The edema surrounding the lesion increased over time, up to the 72 hours studied. These data provide important information on the development of lesion appearance, which may be applied in the development of real-time magnetic resonance imaging monitoring of radiofrequency lesion formation. This technique associated with electrophysiological response and the real-time visualization of the anatomic correlation of the probe may allow for a very precise and selected lesion in the central nervous system for the treatment of functional disorders and brain tumors.
Assuntos
Encéfalo/patologia , Encéfalo/cirurgia , Imageamento por Ressonância Magnética , Radiocirurgia , Adolescente , Adulto , Idoso , Criança , Feminino , Gadolínio , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-OperatórioRESUMO
The authors sought to determine whether there are any heating effects of 1.5-T MR scanning upon nickel-chromium electrodes and to confirm the safety of scanning these electrodes after intracranial surgical implantation in epilepsy patients. Since there was no significant temperature increase of the electrodes tested in their experiments, the authors conclude that nickel-chromium electrodes implanted in the brain are thermally safe for MR scanning.
Assuntos
Encéfalo/anatomia & histologia , Ligas de Cromo , Eletrodos Implantados , Imageamento por Ressonância Magnética , Encéfalo/cirurgia , Epilepsia/diagnóstico , Epilepsia/cirurgia , Humanos , Técnicas In Vitro , Modelos Biológicos , Modelos Teóricos , TemperaturaRESUMO
The mechanism regulating ovarian regression during incubation behavior in the domestic turkey has not been elucidated. This study was designed to determine whether ovarian steroidogenic potential is depressed during gonadal regression associated with the onset of incubation behavior. Hens were housed in floor pens equipped with trap nests that were checked 7 times per day. Hens were grouped, according to nesting frequency and egg production, into the following classifications: laying (laid an egg every day and trapped in the nest only once/day); transitional (laid an egg every day but trapped in the nest 4 or more times/day); and Day 1, Day 3, and Day 5 incubating (no egg for 2, 4, or 6 days, respectively, while trapped in the nest at least 4 times/day). Follicular atresia was evident in the largest preovulatory follicle (F1) in transitional hens, extensive in F1 through the third largest follicle (F3) in Day 1 incubating hens, and extensive in F1 through F7in Day 3 incubating hens. Levels of circulating LH, progesterone (P), androgen (A), and estradiol (E) decreased in transitional hens relative to concentrations in laying hens and remained low thereafter. In contrast, levels of prolactin were greater in Day 3 and Day 5 incubating hens than in laying, transitional, or Day 1 incubating hens. Basal production of P by F1 granulosa cells was lower from Day 1 incubating hens than from the other groups. Production of P in response to porcine-luteinizing hormone (pLH) was greater by cells from transitional and Day 1 incubating hens than from those of laying hens.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Estrogênios/metabolismo , Atresia Folicular/fisiologia , Progesterona/metabolismo , Perus/fisiologia , Androgênios/metabolismo , Animais , Células Cultivadas , Feminino , Células da Granulosa/metabolismo , Hormônio Luteinizante/farmacologia , Comportamento de Nidação/fisiologia , Tamanho do Órgão , Ovário/fisiologia , Oviductos/fisiologia , Células Tecais/metabolismo , Perus/sangueRESUMO
A methodology has been developed for stereotactic investigation of limbic epilepsy using an image-analysis system that simultaneously displays different structural and functional images of the brain. The validity and accuracy of this system were established with phantom studies. Surgical planning and electrode implantation are guided by stereotactic magnetic resonance imaging, digital subtraction angiography, and position emission tomography. This methodology provides the spatiotemporal relationship of cerebral structure and function necessary to identify seizure onset and propagation in human limbic system epilepsy.
Assuntos
Mapeamento Encefálico , Epilepsia do Lobo Temporal/fisiopatologia , Processamento de Imagem Assistida por Computador , Técnicas Estereotáxicas , Humanos , Tomografia Computadorizada de EmissãoRESUMO
An image analysis system was developed for stereotactic neurosurgery that allows the simultaneous display of brain images from different imaging devices obtained in different orientations. The system is based on a stereotactic frame and a microcomputer and features an easy user interface together with point registration and region of interest analysis in three-dimensional space. A dynamic multi-image environment allows for simultaneous display of magnetic resonance, computed tomography, digital subtraction angiography, and positron emission tomography images in multiple windows, adjusted for common coordinates with reference to stereotactic frame fiducial markers. Linkages between images allow information interchange between different modalities and different views: Points and regions defined in one image can be transferred to others, and cursor coordinates in one image can be calculated and dynamically projected in other images. Phantom studies show that the system distortions are minor and that the system is suitable for clinical use. The system provides exceptional advantages over previous imaging procedures for stereotactic surgery.
Assuntos
Encéfalo/patologia , Diagnóstico por Imagem , Processamento de Imagem Assistida por Computador , Técnicas Estereotáxicas , Angiografia Digital , Encéfalo/diagnóstico por imagem , Encéfalo/cirurgia , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética , Modelos Estruturais , Tomografia Computadorizada de Emissão , Tomografia Computadorizada por Raios XRESUMO
The accuracy of stereotactic electrode implantation using MR guidance and a computerized imaging system was compared to the conventional Talairach system, using ventriculography and a stereotactic atlas. A combined methodology of two stereotactic approaches was used, with a modified Leksell and a Todd-Wells frame. The coordinates of temporo-limbic structures and the length of the AC-PC line were measured prior to implantation in 10 epileptic patients undergoing the combined procedure. Relative differences in single and three-dimensional values were obtained for 68 targets within the temporal lobe. Lengths of AC-PC lines were measured in 9 patients. Statistical differences were found for all temporal coordinates, but the AC-PC line did not differ significantly.
Assuntos
Eletroencefalografia/instrumentação , Epilepsia do Lobo Temporal/fisiopatologia , Imageamento por Ressonância Magnética/instrumentação , Processamento de Sinais Assistido por Computador/instrumentação , Técnicas Estereotáxicas/instrumentação , Mapeamento Encefálico/instrumentação , Eletrodos Implantados , Epilepsia do Lobo Temporal/cirurgia , Humanos , Minicomputadores , Psicocirurgia , Lobo Temporal/fisiopatologia , Lobo Temporal/cirurgiaRESUMO
Capacitation of stallion spermatozoa in Tyrode's calcium-free (TCF) medium was assessed. Twelve gel-free ejaculates were collected. After removal from the seminal plasma, cells were washed three times with 0.85% saline containing 0.1% bovine serum albumin (BSA) and resuspended in TCF. Both washing and incubation media were adjusted to pH 8 and 300 to 310 mOsm. Final sperm concentration during incubation was 2 x 10(6) cells/ml. The diluted ejaculates were incubated for 2, 4, 6, 8 and 10 h at 37 degrees C in an atmosphere containing 5% CO(2). Acrosomes were stained with naphthol yellow and erythrocin B initially and after each incubation period and evaluated microscopically. Transmission electron microscopy was used to verify whether normal acrosome reaction was occurring or if cells were degenerating. Penetration of zona-free hamster oocytes was evaluated using 10(3) to 10(4) sperm/ml suspension and coincubating eggs for 3.5 to 4 h with sperm. Penetration tests were done for wash and incubation treatments and recorded positive when swollen sperm heads or male pronuclei were present. Incubation time affected acrosome integrity (P<0.001). Incubation for 8 to 10 h significantly improved acrosome reaction (P<0.001) and the percentage of reacted acrosomes increased sharply after 6 h of incubation (P<0.001). None of the washed sperm penetrated zona-free eggs at zero time, but sperm from all incubation treatments penetrated eggs. A peak penetration rate of 29.9% was observed at 8 h (P<0.001). Results indicate that under the conditions used, the requirement for Ca(++) in the medium for the process of capacitation and acrosome reaction can be substituted for by elevated pH.
RESUMO
Porcine vasoactive intestinal polypeptide (VIP; 10(-9) to 10(-7) M) was a potent stimulator of prolactin (PRL) release by anterior pituitary cells from immature and laying turkey hens. Basal and VIP-induced PRL release of cells from laying hens were diminished (P less than 0.05) when the cells were cultured for 48 hr in the presence of charcoal-stripped laying hen serum, but not when the cells were cultured in the presence of whole laying hen serum. This change in VIP-induced PRL release was not evident when cells were derived from immature hens. Basal PRL release by cells from laying hens was not altered by the presence of estradiol (E2; 10(-12) to 10(-5) M), although such release was generally enhanced in cultures of cells from immature hens containing E2. The presence of E2 enhanced (P less than 0.05) the magnitude of the VIP-induced PRL release by cultures of cells from laying hens and diminished (P less than 0.05) the magnitude of this release in cultures of cells from immature hens. Cells from immature and laying hens exposed to progesterone (P4; 10(-5) M) for 96 hr exhibited enhanced basal PRL release, though lower P4 concentrations had no effect. Utilizing cells from laying hens, P4 exposure for 24 hr resulted in diminished (P less than 0.05) VIP-induced PRL release, while P4 exposure for 96 hr resulted in markedly enhanced (P less than 0.05) VIP-induced PRL release. Basal PRL release was generally not altered by the presence of testosterone (T). The VIP-induced PRL release by cells derived from immature and laying hens was diminished (P less than 0.05) by the presence of T. Prolactin release in the turkey is likely modulated by gonadal steroids acting directly on the cells of the anterior pituitary.
Assuntos
Hormônios Esteroides Gonadais/farmacologia , Adeno-Hipófise/metabolismo , Prolactina/metabolismo , Perus/metabolismo , Peptídeo Intestinal Vasoativo/farmacologia , Animais , Sangue , Células Cultivadas , Carvão Vegetal , Estradiol/farmacologia , Feminino , Adeno-Hipófise/efeitos dos fármacos , Progesterona/farmacologia , Testosterona/farmacologiaRESUMO
The magnitude of luteinizing hormone (LH) release during a 3-hr test incubation was diminished (P less than 0.05) when anterior pituitary cells from young turkeys were cultured for 24 to 120 hr. This trend was evident with basal LH release and with LH release induced by luteinizing hormone-releasing hormone (LH-RH) or hypothalamic extract. Anterior pituitary cells were cultured with various concentrations (10(-14) to 10(-6) M) of estradiol (E2), progesterone (P4), or testosterone (T) for 24 hr and then exposed to LH-RH or control medium for 3 hr, still in the presence of steroids. Basal LH release was potentiated (P less than 0.05) when cells were cultured with 10(-8) or 10(-6) M T, but not with E2 or P4. When cells were cultured with E2, LH release in the presence of 10(-8) M LH-RH was enhanced (P less than 0.05) in a dose-dependent fashion. LH-RH mediated LH release was also enhanced (P less than 0.05) when cells were cultured with 10(-8) M P4 or 10(-6) M T. Gonadal steroids can act directly on the anterior pituitary of the young domestic turkey to modulate LH release, with T enhancing basal LH release and E2 potentiating LH-RH-mediated LH release.
Assuntos
Gônadas/metabolismo , Hormônio Luteinizante/metabolismo , Adeno-Hipófise/metabolismo , Esteroides/fisiologia , Perus/fisiologia , Animais , Células Cultivadas , Estradiol/fisiologia , Feminino , Hormônio Liberador de Gonadotropina/fisiologia , Masculino , Progesterona/fisiologia , Radioimunoensaio , Testosterona/fisiologiaRESUMO
Two experiments were conducted to evaluate the effect of estradiol benzoate (EB), progesterone (P), ovine prolactin (oPrl), or their combinations on temporal patterns of serum luteinizing hormone (LH) and Prl and on nesting behavior in adult ovariectomized female turkeys. Levels of serum LH were initially reduced (p greater than 0.05) by the steroid treatments, while continuation of treatments induced surges of LH to levels comparable to pretreatment levels. Administration of steroid increased (p less than 0.05) levels of serum Prl, which persisted until termination of treatments. Administration of oPrl had no effect on levels of serum LH but blunted the steroid-induced release of Prl. Neither EB, P, nor oPrl treatments alone nor a combination of EB + P elicited nest occupation. Nest occupation was observed after administration of P only in turkeys pretreated with EB. Administration of oPrl maintained and advanced the P-induced nesting to persistent nesting behavior (incubation behavior). Once persistent nesting behavior was established, hormonal treatments were terminated, yet nesting behavior was maintained and serum samples showed increasing levels of Prl and decreasing levels of LH. It is suggested that incubation behavior in the female turkey is facilitated by the combined action of estradiol, P, and Prl.
Assuntos
Estradiol/farmacologia , Hormônio Luteinizante/sangue , Comportamento Materno , Progesterona/farmacologia , Prolactina/farmacologia , Animais , Interações Medicamentosas , Feminino , Ovariectomia , Prolactina/sangue , PerusRESUMO
Three experiments were conducted to evaluate the effect of immobilization on plasma prolactin (PRL) levels in the immature turkey. Acute immobilization for 120 min resulted in elevated PRL levels (P less than 0.05) starting 15 min after the onset of immobilization. Release from immobilization caused PRL levels to return to those of the nonimmobilized controls by 120-180 min following replacement of the turkeys in cages. Repeated immobilization for 3 or 5 consecutive days diminished PRL response (P less than 0.05) to subsequent immobilization. It is suggested that the PRL controlling mechanism(s) of the young turkey is both susceptible and able to habituate to changes induced by immobilization stress.
Assuntos
Imobilização , Prolina/sangue , Perus/fisiologia , Animais , Hormônio Luteinizante/sangue , Masculino , Fatores de TempoRESUMO
Intravenous administration of 0.025, 0.25, or 2.5 micrograms/kg thyrotropin releasing hormone (TRH) to 4-week-old female turkeys induced a dose-dependent increase (P = 0.004) in serum prolactin (PRL) 15 min post-treatment. Dispersed anterior pituitary cell cultures were utilized to determine the effect of TRH on cellular release of PRL, luteinizing hormone (LH), and growth hormone (GH). In the first experiment, cells from 13-week-old male turkeys were initially incubated for 24 hr in Medium 199 (M-199) plus 10% turkey serum and then placed in M-199 plus 10(-10) to 10(-4) M TRH for 5 hr. Incubation with TRH produced no change in PRL release from that of spontaneous release (P = 0.854). However, 10(-5) and 10(-4) M TRH induced LH release (P less than 0.0001). The TRH-induced GH response was parabolic (P less than 0.0001), with the maximal release at 10(-8) M. The second experiment, utilizing pituitary cells from 7-week-old females, studied these responses on 3, 5, and 7 days of monolayer incubation. TRH failed to induce a PRL release in all tests (P greater than 0.162), although hypothalamic extract induced a large release (P less than 0.0001) of PRL each time. Both 10(-6) and 10(-4) M TRH induced a LH release on Day 3 while only 10(-4) M did so on Day 5, and none of the doses elicited a release on Day 7. The parabolic GH response generally persisted in all tests.(ABSTRACT TRUNCATED AT 250 WORDS)