The hormonal factors associated with converting a corpus luteum of estrous cycle into pseudopregnancy were studied by measuring LH, FSH, prolactin, estradiol and progesterone levels in decapitated rats during the 4-day comparable time (lights on 0600–0800 hr). During cycle, LH FSH remained low unchanging except afternoon proestrus,when typical proestrous surges observed. In contrast, began to increase D-l, from baseline values 7 pg⁄ml approximately 15–20 pg/ml. These maintained until D-2,...

Maternal obesity is thought to increase the offspring's risk of juvenile and metabolic diseases; however, mechanism(s) whereby excess maternal nutrition affects fetal development remain poorly understood. Here, we investigated in nonhuman primates effect chronic high-fat diet (HFD) on systems. We found that offspring from both lean obese mothers chronically consuming a HFD had 3-fold liver triglycerides (TGs). In addition, HFD-fed (O-HFD) showed increased evidence hepatic oxidative stress...

Childhood obesity is associated with increased risk of behavioral/psychological disorders including depression, anxiety, poor learning, and attention deficient disorder. As the majority women child-bearing age are overweight or obese consume a diet high in dietary fat, it critical to examine consequences maternal overnutrition on development brain circuitry that regulates offspring behavior. Using nonhuman primate model diet-induced obesity, we found high-fat (HFD) consumption caused...

The ability of luteinizing hormone-releasing hormone (LHRH) neurons to express the oncogene c-fos was examined during estrous cycle in rats. immunocytochemical localization c-fos-encoded antigen, Fos, coupled with LHRH. LHRH showed no Fos immunoreactivity diestrus-1, diestrus-2, estrus, or morning proestrus. However, expressed from 1600 2200 hours timing onset expression proestrus suggests a strong correlation increased LH secretion. Pentobarbital, which blocks preovulatory surge, blocked...

Agouti-related protein (AGRP) is a recently described homolog of the skin agouti protein. AGRP transcribed primarily in adrenal and hypothalamus high affinity antagonist neural melanocortin-3 melanocortin-4 receptors. The perikarya expressing messenger RNA are found arcuate nucleus rat rhesus monkey. Using polyclonal antibody against pharmacologically active domain (amino acids 83–132), we have also characterized distribution AGRP-immunoreactive neurons both species. major fiber tracts...

Cervical stimulation in the rat institutes a pattern of prolactin secretion consisting two daily surges, one diurnal and nocturnal, which continue for greater part pseudopregnancy. This contrasts with diestrous day 1–2 interval estrous cycle wherein levels are low relatively unchanging. A variety noxious procedures such as aortic cannulation serial blood sampling, sham ovariectomy surgical cuts hypothalamus selectively temporarily suppresses surges pseudopregnancy; nocturnal remained...

The hypothalamic melanocortin system, which controls appetite and energy expenditure, develops during the third trimester in primates. Thus, maternal nutrition health may have a profound influence on development of this system. To study effects chronic high-fat diet (HFD) system fetal nonhuman primate, we placed adult female macaques either control (CTR) or HFD for up to 4 yr. A subgroup animals was also switched CTR fifth year (diet reversal). Third-trimester fetuses from mothers showed...

The pattern of plasma prolactin following uterine cervical stimulation consists two surges each day, one nocturnal, occurring between 0100−0900 h (lights on 0600−1800 h), and diurnal, 1500−2100 h. This continued throughout pseudopregnancy; the last surge was observed morning day 11 (day 1 taken as first diestrus pregnancy or pseudopregnancy). Prolactin levels remained low thereafter until spontaneous proestrous afternoon 12, signalling onset a new estrous cycle. In contrast, daily did not...

To identify possible factors associated with lactation that may be involved in the suppression of GnRH neuronal function, we have examined whether induces changes arcuate nucleus focusing on neuropeptide-Y (NPY) and POMC activity. Animals were studied during diestrous day 1 estrous cycle or 10 postpartum. Lactating animals had their litters adjusted to eight pups 2 Brain tissue was removed measure NPY peptide content median eminence (ME) ME-arcuate (ME-ARC) quantify mRNA by situ...

The perinatal environment plays an important role in programming many aspects of physiology and behavior including metabolism, body weight set point, energy balance regulation predisposition to mental health-related disorders such as anxiety, depression attention deficit hyperactivity disorder. Maternal health nutritional status heavily influence the early have a long-term impact on critical central pathways, melanocortinergic, serotonergic system dopaminergic systems. Evidence from variety...

We have examined testicular and pituitary function in inbred CD-F rats DBA/2J mice with chronic hyperprolactinemia induced by grafting 4 anterior pituitaries from adult females of the same strain under kidney capsule. Eight were given isografts 9 sham-operated; blood samples collected at 4-7 week intervals, animals killed 6 months later. One month after surgery, PRL levels grafted elevated (348 +/- 15 vs. 94 11 ng/ml; P less than 0.001), LH depressed (16 3 59 but T not affected (1.0 0.1 1.1...

The relative effects of the suckling stimulus and ovarian steroids on gonadotropin inhibition during lactation were studied in intact ovariectomized lactating rats. On Day 2 postpartum, litter sizes adjusted to 0 or 8 pups ovariectomy was performed. Serum LH concentrations lactators barely detectable approximately five-fold lower than basal cycling levels reported previously by this laboratory. pituitary gradually increased but did not differ markedly from until Days 15 20 postpartum. At all...

Childhood obesity increases the risk of adult and diabetes, suggesting that early overnutrition permanently programs altered energy glucose homeostasis. In present studies, we used a mouse model to investigate whether susceptibility insulin resistance in response high-fat diet (HFD). Litters from Swiss Webster dams were culled three [chronic postnatal (CPO)] or 10 (control) pups then weaned onto standard chow at day (P) 23. At 6 wk age, subset mice was placed on HFD, tolerance examined 16–17...

Lactation results in negative energy balance the rat leading to decreased gonadotrophin-releasing hormone (GnRH) release and anoestrus. Inhibited GnRH may be a result of stimulatory tone from neuropeptides critical for neuronal activity, such as kisspeptin (Kiss1) neurokinin B (NKB). The present study aimed identify projections colocalised population Kiss1/NKB cells arcuate nucleus (ARH) using double-label immunohistochemistry determine where this directly regulate activity. Additionally,...

The physiological role of thyrotropin-releasing hormone (TRH) in the regulation thyrotropin (thyroid-stimulating hormone, TSH) and prolactin (Prl) secretion has been assumed but not proven. Stimulation their release requires pharmacologic doses TRH. Lesions hypothalamus usually induce an inhibition TSH increase Prl. To determine whether TRH is essential for Prl rat, 0.1 ml antiserum (TRH-Ab) or normal rabbit serum was administered to normal, thyroidectomized, cold-exposed, proestrus rats...

The luteotropic stimuli necessary to transform the corpus luteum of estrous cycle into a psuedopregnancy on morning diestrus-2 (Day 2), as reflected by dramatic divergence in progesterone secretion, were studied 1 was taken first day diestrus pseudopregnancy). requirement prolactin (PRL) stimulus determined inhibiting diurnal and nocturnal PRL surges that occur immediately before during progesterone. Following cervical stimulation, mg 2-Br-alpha-ergocryptine (EC) injected at 1100 2300 h Day...

Objective To utilize a nonhuman primate model to examine the impact of maternal high-fat diet (HFD) consumption and pre-pregnancy obesity on offspring intake palatable food whether HFD impaired development dopamine system, critical for regulation hedonic feeding. Methods The exposure diets varying composition was assessed after weaning. influence prefrontal cortex-dopaminergic system at 13 months age also examined. Results During preference test, exposed displayed increased high in fat sugar...

Neuropeptide Y (NPY) neurons in the arcuate nucleus of hypothalamus (ARH) have been shown to play an important role modulating LH secretion. One mechanism by which ARH NPY system may regulate secretion is GnRH neuronal function. Thus, present study examined whether provided direct input cell bodies preoptic area (POA), as well their nerve terminals median eminence (ME). The possible involvement Y1 receptor subtype mediating effects was also investigated. Lactating rats were used these...

Abstract During lactation, the levels of neuropeptide Y (NPY), which plays an important role in mediating food intake, are significantly elevated a number hypothalamic areas, including arcuate nucleus (ARH). To identify additional systems that might be increase intake and alterations energy homeostasis during present studies examined expression agouti-related protein (AGRP), recently described homologue skin agouti protein. AGRP is found hypothalamus has been suggested to play regulation...

To ascertain whether changes in the pattern of GnRH release from hypothalmus occur during 4-day rat estrous cycle, LH was characterized on each day and results were interpreted light pituitary responsiveness to previously described by this laboratory time. Blood samples taken intact, freely moving rats via venous catheters at 6- 10-min intervals for 3–4 h. pulse height interpulse interval quantified transition afternoon pfoestrus tonic preovulatory surge detailed. The effects estrus small...