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PubMedDate not supplied

Distribution of epidermal growth factor binding sites in the adult rat anterior pituitary gland.

The distribution of epidermal growth (EGF) binding sites was studied in the pituitary gland using light and electron microscope autoradiography which was performed at different time intervals (2 to 60 min) after intravenous (IV) injection of [125I]EGF into adult rats. At the light microscopic level, the labeling was found over cells of the anterior pituitary gland. The time-course study performed by light microscope autoradiography showed that the maximal values were reached at the 2 min time interval. At this time interval, most silver grains were found at the periphery of the target cells. After, the number of silver grains decreased progressively and the localization of silver grains in the cytoplasm indicated the internalization of [125I]EGF. Electron microscope autoradiography showed that labeling was mostly restricted to mammotrophs and somatotrophs. Control experiments indicated that the autoradiographic labeling was due specific interaction of [125I]EGF with its binding site. These results indicate that EGF binding sites are present in at least two anterior pituitary cell types and suggest that EGF can exert a physiological role in the pituitary gland.

Animals↗
PubMed1986

Suppression of glutathione S-transferases in rat seminal vesicles or pituitary glands.

We have studied the tissue-specific expression of GSH S-transferases in rat seminal vesicles and pituitary glands by in vitro translation and immunoprecipitation. The major GSH S-transferase subunit expressed in rat seminal vesicles belongs to the Yb mobility class whose expression diminishes when the rats are treated with pentobarbital. The pattern of GSH S-transferase expression in the pituitary gland is very similar to that of the rat brain with Yb size subunit(s) predominant. The Y beta size subunit is also expressed together with the Yc and Y delta subunits. The expression of GSH S-transferases was drastically reduced in pituitary gland poly(A) RNAs from diethylstilbestrol-treated, ovariectomized female rats. Xenobiotics such as phenobarbital, 3-methylcholanthrene, and trans-stilbene oxide induce rat liver GSH S-transferase activities, especially the Ya- and Yb-subunit containing isozymes. Induction of GSH S-transferases by a combination of the three xenobiotics is neither additive nor synergistic, however. Our results clearly demonstrate that GSH S-transferase expression in seminal vesicles and pituitary glands can be suppressed by phenobarbital and diethylstilbestrol, respectively. Our findings suggest that different GSH S-transferase isozymes respond differently to various xenobiotics. Both induction and suppression occur in rats treated with xenobiotics. This notion helps to explain the lack of additive or synergistic induction in rats treated with more than one xenobiotic.

Animals↗
PubMed2002

Are folliculo-stellate cells in the anterior pituitary gland supportive cells or organ-specific stem cells?

Folliculo-stellate cells (FS-cells) in the anterior pituitary gland are star-shaped cells and form tiny follicles. FS-cells are positive for S-100 protein and produce many cytokines or growth factors, such as interleukin-6 (IL-6), leukemia inhibitory factor (LIF), basic fibroblastic growth factor (bFGF) and vascular endothelial cell growth factor (VEGF). Therefore, it is generally accepted that FS-cells regulate endocrine cells through these growth factors. FS-cells also exhibit a phagocytotic activity and are known to work as scavenger cells. In addition to these functions, FS-cells are considered to have some unknown functions. In order to reveal the biological significance of FS-cells in the anterior pituitary gland, we performed a morphological study and obtained some new findings. First, we were interested in the colloid formation in the senescent porcine pituitary gland. We analyzed the colloids and found that clusterin is a major protein in them. We also found that the accumulation of clusterin in the colloids is related to the phagocytotic activity of FS-cells. In our next study, we found that FS-cells have the potential to differentiate into striated muscle cells. From FS-cells show multi-potent cell character and other cytological evidence, we propose that FS-cells are candidate of organ-specific stem cells in the anterior pituitary gland.

Animals↗
PubMed1990

In vivo assessment of pituitary gland volume with magnetic resonance imaging: the effect of age.

We used sagittal and coronal T1 weighted magnetic resonance images, at 1.5 Tesla, to measure the height, width, length, and cross-sectional area and to generate two estimates of pituitary gland volume in 35 normal volunteers aged 26-79 yr (19 females and 16 males). Subjects over 50 yr of age had significantly smaller pituitary gland height (P = 0.03), area (P = 0.04), and volume (P = 0.04) than those under 50 yr (by two-tailed t test). Overall, age was negatively correlated with pituitary volume (V1: r = -0.51; P = 0.003; V2: r = -0.47; P = 0.008), area (r = -0.43; P = 0.009), and height (r = -0.46; P = 0.005), but not with pituitary length or width. There were no statistically significant differences in pituitary size between men and women (by two-tailed t test). These findings suggest that pituitary gland height provides a good single measure for the assessment of pituitary gland size and that age must be controlled for in studies of pituitary gland size.

Adult↗
PubMed2000

alpha-MSH acetylation in the pituitary gland of the sea bream (Sparus aurata L.) in response to different backgrounds, confinement and air exposure.

MSH is a pituitary hormone derived by post-translational processing from POMC and involved in stress and background adaptation. N-terminal acetylation of MSH to monoacetyl alpha-MSH or diacetyl alpha-MSH increases the bioactivity of the peptide. The aim of this study was to characterize alpha-MSH acetylation in the sea bream (Sparus aurata L.) pituitary gland in response to the stressors air exposure and confinement, as well as in fish adapted for 15 days to a white, gray or black background. Pituitary homogenates were purified by reversed-phase HPLC (RP-HPLC). The alpha-MSH content of fractions was measured by RIA. Immunoreactive RP-HPLC fractions were further analyzed by electrospray mass spectrometry and the peptide sequence determined as SYSMEHFRWGKPV-NH2. In the pituitary gland of sea bream, des-, mono- and diacetyl alpha-MSH were identified. Then plasma alpha-MSH levels were measured in sea bream adapted to different backgrounds. Surprisingly, we found the highest plasma alpha-MSH levels in white-adapted as compared with black-adapted sea bream with intermediate values for gray-adapted fish. This observation is in contrast with results that have been obtained in eel, trout or terrestrial vertebrates. Next, des-, mono- and diacetyl alpha-MSH forms were measured in homogenates of the pituitary gland and in plasma of sea bream exposed to air, to confinement, or to different backgrounds. Monoacetyl alpha-MSH was the predominant form in all control and experimental groups. The lowest content of monoacetyl alpha-MSH relative to des- and diacetyl alpha-MSH was found in white-adapted fish. Levels of des- and diacetyl alpha-MSH forms were similar under all conditions. We observed that monoacetyl alpha-MSH is the most abundant isoform in the pituitary gland after background adaptation, confinement and air exposure, in sea bream. These data indicate that the physiologically most potent isoform of alpha-MSH may vary from species to species.

Acetylation↗
PubMed2004

Estrogens sensitize anterior pituitary gland to apoptosis.

Tissue homeostasis results from a balance between cell proliferation and cell death by apoptosis. Estradiol affects proliferation as well as apoptosis in hormone-dependent tissues. In the present study, we investigated the apoptotic response of the anterior pituitary gland to lipopolysaccharide (LPS) in cycling female rats, and the influence of estradiol in this response in ovariectomized (OVX) rats. The OVX rats were chronically estrogenized with implanted Silastic capsules containing 1 mg of 17beta-estradiol (E2). Cycling or OVX and E2-treated rats were injected with LPS (250 microg/rat ip). Apoptosis was determined by the terminal deoxynucleotidyl-mediated dUTP nick-end labeling (TUNEL) method in sections of the anterior pituitary gland and spleen. Chronic estrogenization induced apoptosis in the anterior pituitary gland. Acute endotoxemia triggered apoptosis of cells in the anterior pituitary gland of E2-treated rats but not of OVX rats. No differences were observed in the apoptotic response to LPS in spleen between OVX and E2-treated rats. The apoptotic response of the anterior pituitary to LPS was variable along the estrous cycle, being higher at proestrus than at estrus or diestrus I. Approximately 75% of the apoptotic cells were identified as lactotropes by immunofluorescence. In conclusion, our results indicate that estradiol induces apoptosis and enables the proapoptotic action of LPS in the anterior pituitary gland. Also, our study suggests that estrogens may be involved in anterior pituitary cell renewal during the estrous cycle, sensitizing lactotropes to proapoptotic stimuli.

Animals↗
PubMedDate not supplied

Morphological changes in the pituitary gland of dogs chronically exposed to exogenous growth hormone.

Growth hormone (GH) synthesis and release from the pituitary is regulated by hypothalamic releasing hormone, insulin-like growth factor-1 (IGF-1), and somatostatin. However, the potential effects of pharmacological doses of exogenous GH on the pituitary are not well studied. To determine the potential chronic effects of exogenous GH on pituitary morphology in dogs, porcine GH (pGH) was administered subcutaneously to 3 groups of dogs (4 animals/sex/group) at doses of 0.025, 0.1, and 1.0 IU/kg/day for 14 wk. A group (4/sex) of dogs served as the vehicle control. The pituitaries from all dogs were weighed and fixed in appropriate fixatives for light and electron microscopic examination; in addition, cells of the pars distalis were quantitated by a point counting method following immunostaining to identify cells containing GH, prolactin (PRL), and adrenocorticotrophic (ACTH) hormones. Administration of pGH resulted in a statistically significant (p < or = 0.05) increased pituitary weight through the high dose. By light microscopy (LM), hypertrophy of pars distalis cells was evident in mid- and high-dose female dogs. The pituitaries of dogs given the lowest dose (0.025 IU/kg/day) of pGH were not remarkable based on weight and LM findings. In addition, transmission electron microscopic (TEM) examination of the pituitary gland of high-dose demonstrated, in both sexes, pituitary cells with variably dilated rough endoplasmic reticulum and decreased numbers of secretory granules; some of these cells reacted positively to GH immunostaining. Quantitative analysis of the pituitary gland of high-dose males and females showed an increase in the absolute volume of all cell populations studied: GH-, PRL-, and ACTH-positive cells. Based on the LM and TEM findings, the increased volume of the cell populations studied is likely related to cellular hypertrophy. The expected elevation in serum GH levels following repeated administration of pGH and an associated elevation in serum IGF-1 levels resulted in morphologic changes in the pituitary gland of dogs given high doses (> or = 0.1 IU/kg/day) of pGH; these observations differed from the reported findings in pituitaries of transgenic mice secreting large quantities of bovine GH.

Adrenocorticotropic Hormone↗
PubMed1989

Endocrine regulation of cytochrome P-450 in the rat brain and pituitary gland.

In an effort to understand the physiological functions of cytochrome P-450 in the central nervous system and pituitary gland, we evaluated changes in the level of the enzyme as a function of the endocrine status of rats and the ability of these tissues to synthesize or degrade steroids. The P-450 content of microsomes prepared from the hypothalamic preoptic area (HPOA), the olfactory lobes and the cerebrum was 0.040 +/- 0.009 and in the pituitary gland 2.2 +/- 0.6 (S.D.) nmol/g tissue. The P-450 content of the HPOA and olfactory lobes, but not of the rest of the cerebrum, was influenced by the endocrine status of rats. In microsomes it increased five- to tenfold over control levels during late pregnancy in the olfactory lobes and during lactation in the HPOA, and in both brain regions treatment of rats with 5 alpha-dihydrotestosterone (DHT) caused an eight- to tenfold increase in the P-450 content. Androstenedione was not a good substrate for brain P-450. The level of androstenedione 19-hydroxylase in the olfactory lobe microsomal fraction was 0.50 +/- 0.06 nmol 19-hydroxyandrostenedione formed/g tissue per h. This activity was tenfold lower in other brain areas and was not detectable in the pituitary gland. The rate of aromatization of androstenedione to oestradiol in the HPOA and olfactory lobe of lactating rats was 0.46 +/- 0.14 and 0.38 +/- 0.05 pmol/oestradiol formed/g tissue per h respectively. 5 alpha-Androstane-3 beta,17 beta-diol (A-5 alpha-3 beta,17 beta-diol) was a much better substrate for P-450 throughout the brain and pituitary gland.(ABSTRACT TRUNCATED AT 250 WORDS)

5-alpha-Dihydroprogesterone↗
PubMed2006

[Evaluation of the tumor of the pituitary gland (hypophysis) between 2000-2005. On the intensive care of The Endocrinology Clinic of the Clinical Center of the University of Sarajevo].

INTRODUCTION: Tumors of the pituitary gland can be adenomas, and more often, cancers, representing 10-15% of intracranial neoplasm. We make a difference between them according to their size, expansion, hormone's activity and local and endocrinological manifestations. The goal of the research was to reveal the presence of tumors of the pituitary gland in the period 2000-2005 among patients hospitalized on the Intensive Care of the Endocrinology Clinic. PATIENTS AND METHODS: Data from anamnesis of all patients with verified tumor of the pituitary gland between 2000.-2005 were used in the research work. RESULTS: Total number of patients with the tumor of pituitary gland was 40, 29 women and 11 men, and 35 % of patients were aged between 45 and 60. Main symptoms: headache -16, eye trouble -17, sexual dysfunction -8, growth of acres -5, and others symptoms -8 patients. There were 23 (57,5%) cases of micro adenoma and 17 (42,5 %) macro adenomas. From the total number of patients 23 were operated, 8 micro adenomas and 15 macro adenomas. The number of secreting adenomas was 25 (62,5 %) and 15 (37,5 %) were non-secreting. Secreting adenomas were: prolactinomas--14, acromegalies -7, Cushing syndromes -2, TSH producing -2. Non-secreting adenomas were: craniopharyngeomas--11, meningiomas -2, and 2 non-secreting micro adenomas. Most of prolactinomas were treated with drugs, and 3 cases of prolactinoma were operated. 6 cases of acromegaly were operated and 1 micro adenoma is still under medical supervision, with the therapy of bromocriptine. 3 of those patients have the residuum, and 4 of them have high level of hGH. 11 craniopharyngeomas were operated and all patients, except one, are under substitution therapy. 2 meningiomas were operated and those patients are also under substitution therapy. 1 case of TSH producing tumor was operated, but residuum and hyperthyroidism are still presents, and the micro adenoma, for the hyperplasia reason, disappeared with adequate substitution therapy. The Cushing syndrome, confirmed with MRI diagnostics, wasn't operated; it remained under conservative therapy, and in the other case, where we didn't isolate a pathological substrate, the patient exited. CONCLUSION: Tumors of the pituitary gland we mainly treat applying surgery methods, together with post operational substitution therapy or additional therapy with drugs. Only prolactinomas are tumors which are successfully treated with drugs.

Female↗
PubMed1997

[Phenomenon of intrinsic rhythm of luteinizing hormone release from isolated anterior pituitary gland of female rat].

The intrinsic nature of rthymic release of luteinizing hormone (LH) of isolated human and rat anterior pituitary gland reported independently by Macro Gambacciani and Xie in 1987 can be more directly demonstrated by a computer programme of Time Series-HSY Hidden Periodic Analytic Approach for continuous monitoring the LH output of the perfusate from a perfusion system with in vitro anterior pituitary of SD female rat. The results are as follows: (1) Under various reproductive conditions the average frequency (min/cycle) and amplitude (ng/ml) of the intrinsic rhythm of LH release were quite different: In proestrous group the frequency and amplitude were the highest, being intermediate in the ovariectomized group and lowest in the lactation group. (2) The intrinsic rhythm of LH release could be changed by either peptide or steroid hormones. In proestrous group with 30 min of gonadotropin-releasing hormone (GnRH), stimulation would reduce both frequency and amplitude. In case of lactation, the frequency was unchanged, but amplitude lowered, while in the ovariectomized rat pituitary, the 30 min GnRH stimulation decreased the frequency of release only. The intrinsic rhythm of the LH release could also be influenced by steriod hormones (Ru486 and Anordrin). With 120 min before removal of the anterior pituitary gland the rats receiving i.m. injection of Ru486 (2 mg/kg bw) or Anordrin (2 mg/kg), the results showed that Ru486 decreased frequency, while Anordrin decreased only the frequency to a less extent, both without amplitude affected. (3) Verapamil and EGTA added to the perfusion system did not abolish but only decreased the rhythmic phenomenon by using proestrous pitutary. This suggests that participation of Ca2+ may take place in the intrinsic release of LH. The above results indicated that the intrinsic rhythm of LH release of isolated anterior pituitary gland is different from various reproductive hormonal conditions and capable of being modified by exogenous hormones. The physiological function of the intrinsic rhythm of LH release of anterior pituitary gland remains to be elucidated.

Animals↗
PubMed1990

A brain magnetic resonance imaging study of pituitary gland morphology in anorexia nervosa and bulimia.

Magnetic resonance imaging (MRI) of the brain was used to examine the morphology and dimensions of the pituitary gland in 18 patients with eating disorders (8 anorectics and 10 bulimics), in comparison with 13 healthy volunteers. None of the 18 patients with anorexia or bulimia had any radiological evidence suggestive of pituitary macroadenoma, cyst, or empty sella. Measurements revealed that the anorectics and bulimics had smaller pituitary gland cross-sectional areas (p less than 0.05) and smaller pituitary gland heights, compared with healthy controls. These preliminary findings in anorectics and bulimics are suggestive of pituitary atrophy secondary to nutritional or endocrine alterations, rather than a primary pituitary pathology.

Adolescent↗
PubMed1997

Differential Fos expression induced by IL-1beta and IL-6 in rat hypothalamus and pituitary gland.

IL-1beta has been implicated in central nervous system effects, including activation of the hypothalamic-pituitary-adrenal axis. Less is known concerning the role of IL-6 in brain. To compare and contrast IL-1beta and IL-6 effects on brain, rats were administered intraperitoneal injections of IL-1beta, IL-6 or control vehicle (3-8 microg/rat), perfused 150-180 min post-injection, and brains and pituitaries were processed for Fos immunolabeling. IL-1beta induced Fos expression in corticotrophin-releasing factor (CRF) neurons of paraventricular nucleus (PVN) of the hypothalamus, and anterior pituitary gland. IL-6 also induced immunolabeled Fos in the anterior pituitary gland, however, it did not induce Fos expression in CRF neurons of PVN. Data suggest that IL-6 may directly activate the anterior pituitary gland, whereas IL-1beta may exert its effect on the pituitary directly and/or indirectly via activation of CRF neurons in the PVN.

Animals↗
PubMed1997

Involvement of glucocorticoid-induced factor(s) in the stimulation of growth hormone expression in the fetal rat pituitary gland in vitro.

The mechanism by which glucocorticoids induce GH expression between embryonic days 18 and 19 (E18-19) in the fetal rat pituitary gland was examined with an in vitro organ culture system. Twenty-four hour incubation of E18 pituitary glands in serum-free medium containing either dexamethasone (DEX, 5-50 nM) or corticosterone (0.55 microM) resulted in a conspicuous accumulation of GH messenger RNA (mRNA), whereas no spontaneous expression of GH mRNA was noted without glucocorticoid. Triiodothyronine (1 nM) alone weakly induced GH mRNA but increased the effect of DEX 2-fold. The GH mRNA accumulation was not observed after 5 or 10 h incubation with DEX. However, a 10-h incubation with DEX followed by 14 h chase incubation without DEX resulted in apparent induction of GH mRNA. The induction of GH mRNA by DEX was completely inhibited by puromycin. These data, taken as a whole, suggest that the induction of GH mRNA by DEX in the fetal pituitary gland is not a direct effect of DEX on the GH gene but is mediated by a factor that is synthesized in the pituitary gland in response to DEX. Both immunoblot and RNase protection assays suggested that this factor is not pit-1, which is known to be required for GH mRNA expression.

Animals↗
PubMed1994

Vasopressin-binding sites in the pig pituitary gland: competition by novel vasopressin antagonists suggests the existence of an unusual receptor subtype in the anterior lobe.

Arginine vasopressin (AVP) acts in the pituitary gland, in synergy with corticotrophin-releasing factor, to induce ACTH release in response to stressful stimuli. Pituitary AVP receptors in the rat are coupled to phospholipase C, as are the so-called V1-type AVP receptors. The present study examined [3H]AVP binding in membranes prepared from the anterior lobe of the pituitary gland of the pig. [3H]AVP, alone or in competition with analogues, bound to sites in the pig anterior lobe which are pharmacologically similar to those described previously by others in the rat pituitary gland. For comparison, the same competition studies were performed on membrane preparations from the rat liver which contain the classic V1-type AVP receptor. Pituitary and liver AVP-binding sites were dissimilar; both cyclic and linear V1 antagonists had, in general, a much lower affinity for pituitary AVP-binding sites than for those in the liver. Thus, Phaa-D-Tyr(Et)-Phe-Gln-Asn-Lys-Pro-Arg-NH2 (Phaa = phenylacetyl) has a 2500-fold greater affinity for the latter (negative logarithm of inhibition constant (pKi) = 9.64) than for the former (pKi = 6.22). One linear antagonist, Pa-D-Tyr-Phe-Val-Asn-Arg-Pro-Arg-Arg-NH2 (Pa = propionyl) had about equal affinities for liver and pituitary membranes (pKi = 6.39 and 6.53 respectively). Another compound, Phaa-D-Tyr-Phe-Val-Asn-Arg-Pro-Arg-Arg-NH2 had the highest affinity found to date for binding to AVP sites in the pituitary (pKi = 7.43). These findings suggest some ideas for the design of more potent and/or selective AVP analogues acting in the pituitary gland.

Amino Acid Sequence↗
PubMed2003

Dopaminergic modulation of nNOS expression in the pituitary gland of male rat.

Nitric oxide is an unconventional transmitter since it is not transported and released by exocytosis. In the pituitary gland, nitric oxide is locally synthesised by gonadotroph and folliculo-stellate cells. Dopamine, the principal central inhibitory signal in prolactin release, may exert its inhibitory effects by stimulation of nitric oxide production. However, the effects of dopaminergic modulation on nitric oxide-producing pituitary cells have not been analysed. Therefore, we examined the effects of intraventricular administration of the dopamine antagonist haloperidol (40 microg) on the pituitary expression of neuronal nitric oxide synthase (nNOS) in male adult rats. In untreated and control animals, nNOS-positive cells were very similar. Two types of nNOS-positive cells appeared in the pars distalis: round or polygonal cells and stellate cells. Although some isolated cells were found, the nNOS-positive cells commonly appeared grouped in clusters close to blood vessels. nNOS immunoreactivity appeared as a uniform staining throughout the cytoplasm, including cell prolongations. The number and size of nNOS-expressing cells in the pituitary gland decreased significantly after treatment with haloperidol (p<0.01). To evaluate the potential direct effect of dopamine on pituitary cells, pituitary monolayer cultures were treated with dopamine during a time-course of 12 h. Our in vitro studies revealed that dopamine increases the percentage of nNOS-positive cells and augments cellular area (p<0.05). These results demonstrate that: (1) treatment of rats in vivo with a dopamine antagonist significantly decreases expression of nNOS in the pituitary and (2) in vitro dopamine exerts a direct effect on pituitary cultures by increasing nNOS-positive cells. Thus, these findings suggest that dopamine may function as a physiological stimulator of nNOS expression in the rat pituitary gland.

Animals↗
PubMed1993

Glucocorticoid receptor colocalization with pituitary hormones in the rat pituitary gland.

The presence of glucocorticoid receptor (GR) in the anterior lobe of the pituitary gland has previously been demonstrated, but the exact cell types expressing GR have not yet been characterized. In this study, we demonstrate the colocalization of GR and pituitary hormones in the rat pituitary gland by using an immunocytochemical double-labelling method. The majority of anterior lobe corticotropin-immunoreactive and growth hormone-immunoreactive cells contained GR-like immunoreactivity. Cells of the intermediate lobe showed intensive ACTH-like immunoreactivity but did not express GR. The glycoprotein hormones thyroid-stimulating hormone, follicle-stimulating hormone and luteinizing hormone were colocalized with GR to a lesser degree; approximately one-half of the cells exhibited immunoreactivity to these hormones contained GR. By contrast, only a minority of the prolactin-immunoreactive cells expressed GR. Our results suggest that glucocorticoids may differentially regulate the secretion and/or synthesis of these pituitary hormones by directly affecting the hormone-producing cells of the anterior pituitary.

Animals↗
PubMed1993

Denervation of the rat posterior pituitary gland: validation of a stereotaxic method.

A stereotaxic surgical method was developed for interrupting the nerve fibres running through the rat pituitary stalk to the posterior pituitary gland without obliterating the hypothalamo-pituitary portal circulation. The pituitary stalk was compressed by the blunt tip of an L-shaped rotating knife. Successful operations produced mild diabetes insipidus, disappearance of arginine vasopressin from the neural lobe, accumulation of arginine vasopressin and neurosecretory material in the pituitary stalk and no infarction in the anterior lobe of the pituitary gland. In female rats, the oestrous cycle was only temporarily disturbed. Plasma prolactin and corticosterone levels were high during the first 24 h after the stalk compression but returned to normal baseline levels from the second day after the operation. One week after the operation plasma adrenocorticotropin and prolactin levels were in the control range while plasma alpha-melanocyte-stimulating hormone was elevated. Denervation of the posterior pituitary gland may help in studying the neural control of intermediate lobe function and the role of the neural lobe in various endocrine conditions, and may serve as a model for lesions of the pituitary stalk and formation of ectopic neurohypophysis in the human.

Animals↗