Evidence for the involvement of central catecholaminergic mechanisms in mediating the preovulatory surge of luteinizing hormone in the domestic hen

1982 ◽  
Vol 94 (2) ◽  
pp. 295-304 ◽  
Author(s):  
P. G. Knight ◽  
S. C. Wilson ◽  
R. T. Gladwell ◽  
F. J. Cunningham
Keyword(s):  
Steady State ◽  
Luteinizing Hormone ◽  
Pharmacological Treatments ◽  
Ovulatory Cycle ◽  
Lh Surge ◽  
Dopaminergic Mechanisms ◽  
Lh Release ◽  
Noradrenaline And Adrenaline ◽  
Domestic Hen ◽  
Catecholaminergic Mechanisms

The effects of various pharmacological treatments, designed to perturb central catecholaminergic neurotransmission, on the pattern of LH release during the preovulatory period in the domestic hen were studied. Treatment of hens with either l-dihydroxyphenylalanine or diethyldithiocarbamate which raised the concentration of dopamine in the hypothalamus by 42 and 110% respectively, or with apomorphine, attenuated the preovulatory surge of LH. In contrast, treatment with either α-methyl-p-tyrosine which produced a 65% decline in the concentration of dopamine in the hypothalamus without affecting the concentrations of noradrenaline or adrenaline or treatment with pimozide did not affect the LH surge. While treatment with propranolol was similarly ineffective, phenoxybenzamine attenuated the LH surge to a marked extent. These observations suggest that the preovulatory surge of LH in the hen is influenced by facilitatory α-adrenergic and inhibitory dopaminergic mechanisms. Evidence to corroborate these findings was sought by determining the steady-state concentrations of dopamine, noradrenaline and adrenaline in five discrete diencephalic regions of the hen throughout the ovulatory cycle.

CHANGES IN PLASMA CONCENTRATIONS OF LUTEINIZING HORMONE AFTER INJECTION OF PROGESTERONE AT VARIOUS TIMES DURING THE OVULATORY CYCLE OF THE DOMESTIC HEN (GALLUS DOMESTICUS)

1975 ◽  
Vol 67 (1) ◽  
pp. 59-70 ◽  
Author(s):  
SUSAN C. WILSON ◽  
P. J. SHARP
Keyword(s):  
Luteinizing Hormone ◽  
Plasma Concentrations ◽  
Gallus Domesticus ◽  
Ovulatory Cycle ◽  
Lh Surge ◽  
Incremental Change ◽  
The Mean ◽  
Domestic Hen

SUMMARY Changes in plasma LH concentrations after i.m. injections of 0·5 mg progesterone/kg at various stages of the ovulatory cycle were measured by radioimmunoassay. Four types of response were observed. (1) When the steroid was injected between 4 h after and 12 h before an ovulation, LH levels started to rise after 15–45 min and reached peak values within 90–120 min. The mean maximal incremental change in the level of LH was 1·58 ± 0·10 (s.e.m.) ng/ml (n = 37). (2) In contrast, when progesterone was injected 12–8 h before ovulation, i.e. immediately before a spontaneous pre-ovulatory LH surge, the resulting mean maximal incremental change in LH level, 0·79 ± 0·12 ng/ml (n = 9), was significantly smaller (P < 0·001). (3) If progesterone was injected 8–4 h before ovulation, i.e. when pre-ovulatory LH levels were rising, they immediately started to rise more rapidly and reached peak values within 45 min. The maximal incremental change in the level of LH under these circumstances, 2·34 ± 0·20 ng/ml (n = 12), was significantly greater (P < 0·001 in both cases) than the changes observed in the responses 1 and 2 described above. (4) Levels of LH generally showed no incremental change in response to injections of progesterone given 4–0 h before ovulation, i.e. when pre-ovulatory LH levels were falling. It was concluded that the type of change in plasma LH levels induced by progesterone depended upon the stage of the ovulatory cycle at which the steroid was injected.

EVIDENCE FOR A DOPAMINERGIC COMPONENT IN THE SERIES OF NEURAL EVENTS THAT LEAD TO THE PRO-OESTROUS SURGE OF LH

1977 ◽  
Vol 85 (1) ◽  
pp. 18-24 ◽  
Author(s):  
James A. Clemens ◽  
Frank C. Tinsley ◽  
Ray W. Fuller
Keyword(s):  
Luteinizing Hormone ◽  
Inhibitory Effects ◽  
Brain Dopamine ◽  
Lh Surge ◽  
Lh Release

ABSTRACT The possible participation of dopamine in the neural events that lead to the pro-oestrous surge of luteinizing hormone (LH) was investigated utilizing a dopaminergic ergoline derivative (lergotrile mesylate). Administration of reserpine (2.0 mg/kg, ip) to rats on the day of pro-oestrus depicted brain dopamine and norepinephrine and prevented the LH surge and ovulation. Administration of lergotrile mesylate prior to or at the same time as reserpine prevented the inhibitory effects of reserpine on LH release and on ovulation in about half of the animals. When lergotrile mesylate was given on the morning of pro-oestrus, the LH surge was advanced. The results indicate that there is a dopaminergic component in the series of neural events that precede the surge of LH on prooestrus, and that the dopaminergic stimulus precedes the LH surge by about 4–5 h.

scholarly journals Effect of androgen on Kiss1 expression and luteinizing hormone release in female rats

2017 ◽  
Vol 233 (3) ◽  
pp. 281-292 ◽  
Author(s):  
Kinuyo Iwata ◽  
Yuyu Kunimura ◽  
Keisuke Matsumoto ◽  
Hitoshi Ozawa
Keyword(s):  
Luteinizing Hormone ◽  
Arcuate Nucleus ◽  
Female Rats ◽  
Hormone Release ◽  
Lh Surge ◽  
Continuous Release ◽  
Ovulatory Dysfunction ◽  
Lh Release ◽  
Gonadotrophin Releasing Hormone ◽  
Lh Secretion

Hyperandrogenic women have various grades of ovulatory dysfunction, which lead to infertility. The purpose of this study was to determine whether chronic exposure to androgen affects the expression of kisspeptin (ovulation and follicle development regulator) or release of luteinizing hormone (LH) in female rats. Weaned females were subcutaneously implanted with 90-day continuous-release pellets of 5α-dihydrotestosterone (DHT) and studied after 10 weeks of age. Number of Kiss1-expressing cells in both the anteroventral periventricular nucleus (AVPV) and arcuate nucleus (ARC) was significantly decreased in ovary-intact DHT rats. Further, an estradiol-induced LH surge was not detected in DHT rats, even though significant differences were not observed between DHT and non-DHT rats with regard to number of AVPV Kiss1-expressing cells or gonadotrophin-releasing hormone (GnRH)-immunoreactive (ir) cells in the presence of high estradiol. Kiss1-expressing and neurokinin B-ir cells were significantly decreased in the ARC of ovariectomized (OVX) DHT rats compared with OVX non-DHT rats; pulsatile LH secretion was also suppressed in these animals. Central injection of kisspeptin-10 or intravenous injection of a GnRH agonist did not affect the LH release in DHT rats. Notably, ARC Kiss1-expressing cells expressed androgen receptors (ARs) in female rats, whereas only a few Kiss1-expressing cells expressed ARs in the AVPV. Collectively, our results suggest excessive androgen suppresses LH surge and pulsatile LH secretion by inhibiting kisspeptin expression in the ARC and disruption at the pituitary level, whereas AVPV kisspeptin neurons appear to be directly unaffected by androgen. Hence, hyperandrogenemia may adversely affect ARC kisspeptin neurons, resulting in anovulation and menstrual irregularities.

Evidence of a photoinducible phase for the release of luteinizing hormone in the domestic hen

1982 ◽  
Vol 94 (3) ◽  
pp. 397-406 ◽  
Author(s):  
Susan C. Wilson
Keyword(s):  
Plasma Concentration ◽  
Luteinizing Hormone ◽  
Control Group ◽  
Abrupt Increase ◽  
Threefold Increase ◽  
Main Period ◽  
Lh Release ◽  
Lh Releasing Hormone ◽  
Lh Secretion ◽  
Domestic Hen

Hens raised on a schedule of 8 h light: 16 h darkness (8L : 16D) were exposed to changes in photoperiod at 17 or 18 weeks of age. These involved exposure to either an abrupt increase in photoperiod to 16 h per day or to skeleton photoperiods comprising a main period of 7·75 or 4 h light together with a pulse of 15 min or 4 h light provided at different times during the period of darkness. An increase in photoperiod to 16 h per day stimulated a two- to threefold increase in the plasma concentration of LH within 1–3 days. Interruption of a 7·75L : 16D schedule by 15 min light between 13·75 and 19·75 h after the beginning of the main photoperiod stimulated LH secretion in the immature and adult hen and a higher rate of lay than that of the 8L : 16D control group. There was a significant (P < 0·01) correlation between the concentration of LH in the plasma and the rate of lay. The photostimulated rise in the plasma concentration of LH in the immature hen was not associated with any increase in the responsiveness of the pituitary gland to LH releasing hormone. Of the treatments in which a 15-min pulse of light was provided, the schedules of 7·75L : 10D : 0·25L : 6D and 7·75L : 12D : 0·25L : 4D, which were most effective in stimulating LH release, appeared to be interpreted as 0·25L : 6D : 7·75L : 10D and 0·25L : 4D : 7·75L : 12D respectively. In hens given a 7·75-h main photoperiod, in which phase-reversal did not occur, 15 min light was most stimulatory when given 14–16 h after the begining of the main photoperiod, although not to the same extent as an increase in photoperiod to 16 h per day. In hens for which an 8-h complete photoperiod was changed to a 4-h main photoperiod, together with a further 4-h pulse of light provided at different times during the period of darkness, the period of maximum sensitivity to light occurred 11 h after the onset of the main photoperiod and at this time light stimulated LH release to the same extent as an increase in complete photoperiod from 8 to 16 h per day. Results of this study suggest that the period of maximum photosensitivity shifts its phase after a change in the form of photoperiod and is primarily entrained to dusk.

CONTROL OF THE PREOVULATORY SURGE OF LUTEINIZING HORMONE IN THE HEN (GALLUS DOMESTICUS): THE ROLE OF PROGESTERONE AND ANDROGENS

1978 ◽  
Vol 77 (1) ◽  
pp. 57-65 ◽  
Author(s):  
J. B. WILLIAMS ◽  
P. J. SHARP
Keyword(s):  
Luteinizing Hormone ◽  
Dark Period ◽  
Ovarian Follicle ◽  
Gallus Domesticus ◽  
Ovulatory Cycle ◽  
Blood Samples ◽  
Lh Surge ◽  
Before And After ◽  
Small Rise

Peripheral blood samples were taken from laying hens at frequent intervals during various periods of the ovulatory cycle in order to detect small changes in the concentrations of progesterone and androgen which might be important in initiating the preovulatory release of LH. Blood samples were taken from seven hens at 1 h intervals for 3 h when the ovary contained a mature (C1) follicle and on another occasion, when the largest ovarian follicle was immature. The concentrations of progesterone and androgens in the plasma were 30% higher when there was a mature C1 follicle present in the ovary than when there was not, but this increase was significant (P < 0·05) only for progesterone. The concentrations of progesterone and androgens were also measured in blood samples taken at 30 min intervals during the 3 h before and after the initiation of the first preovulatory LH surge of a sequence. The hens were kept on a lighting schedule of 14 h light/day and the first LH surge of a sequence was initiated at the beginning of the dark period. Just after the onset of darkness there was a small increase in the concentration of LH in the plasma and a subsequent, larger preovulatory release of LH. The first increase in the level of LH was associated with a small rise in the concentrations of androgens and progesterone in the plasma while the preovulatory release of LH was accompanied by a much larger increase in the secretion of these steroids. It is proposed that the increase in the level of LH in the plasma at the onset of darkness stimulates the maturing ovarian follicles to secrete progesterone and androgens and that the quantities of these steroids secreted (particularly of progesterone) depends on the maturity of the largest ovarian follicle. If the largest ovarian follicle is mature, then the increase in the level of LH in the plasma associated with the onset of darkness stimulates the secretion of a quantity of progesterone sufficient to cause the preovulatory surge of LH. A diurnal increase in the concentration of LH in the plasma could, therefore, be responsible for timing the preovulatory surges of LH so that they are only initiated at night.

Pulsatile Luteinizing Hormone (LH) Release during the Progesterone-Induced LH Surge in the Female Rhesus Monkey*

Endocrinology ◽  
1987 ◽  
Vol 120 (6) ◽  
pp. 2265-2271 ◽  
Author(s):  
E. TERASAWA ◽  
C. KROOK ◽  
S. EMAN ◽  
G. WATANABE ◽  
W. E. BRIDSON ◽  
...  
Keyword(s):  
Luteinizing Hormone ◽  
Rhesus Monkey ◽  
Lh Surge ◽  
Female Rhesus ◽  
Lh Release ◽  
Female Rhesus Monkey

An investigation of diurnal and cyclic changes in the secretion of luteinizing hormone in the domestic hen

1983 ◽  
Vol 98 (1) ◽  
pp. 137-145 ◽  
Author(s):  
S. C. Wilson ◽  
R. C. Jennings ◽  
F. J. Cunningham
Keyword(s):  
Luteinizing Hormone ◽  
Diurnal Rhythm ◽  
Laying Hen ◽  
Ovulatory Cycle ◽  
Pronounced Increase ◽  
Threefold Increase ◽  
Steep Decline ◽  
Cyclic Changes ◽  
Lh Secretion ◽  
Domestic Hen

The characteristics of the diurnal rhythm in the concentration of LH in plasma of the domestic hen varied according to age and duration of photoperiod. A pronounced increase in LH was observed at the onset of darkness in immature hens whether maintained on schedules of 16 h light:8 h darkness (16L:8D) or 8L:16D. During weeks 4·5–15 or −17·5 raised concentrations of LH were maintained until 6 and 12 h after the onset of darkness in hens held on 16L:8D and 8L:16D respectively. By 19 weeks of age the diurnal rhythm of LH secretion had changed to resemble more closely that observed in the laying hen. An increase in the concentration of LH in plasma at the onset of darkness was of comparatively short duration and gave way, within 2–3 h, to a steep decline before a further slight increase in LH, which tended to occur at 11–14 h after the onset of darkness. Superimposed on this diurnal rhythm of LH secretion in the laying hen were a one- to threefold increase in the concentration of LH during 8–4 h before ovulation and a much less pronounced increase in LH during 0–8 h after ovulation. The pattern of changes in the concentration of LH in plasma during the ovulatory cycle was not modified by the repeated withdrawal of blood at intervals of 2 h.

scholarly journals Optogenetic Activation of Arcuate Kisspeptin Neurons Generates a Luteinizing Hormone Surge-Like Secretion in an Estradiol-Dependent Manner

2021 ◽  
Vol 12 ◽  
Author(s):  
Xian-Hua Lin ◽  
Geffen Lass ◽  
Ling-Si Kong ◽  
Hui Wang ◽  
Xiao-Feng Li ◽  
...  
Keyword(s):  
Luteinizing Hormone ◽  
Brain Area ◽  
Estradiol Benzoate ◽  
Dependent Manner ◽  
Lh Surge ◽  
Expected Time ◽  
17Β Estradiol ◽  
Stimulation Period ◽  
Lh Release ◽  
Lh Secretion

Traditionally, the anteroventral periventricular (AVPV) nucleus has been the brain area associated with luteinizing hormone (LH) surge secretion in rodents. However, the role of the other population of hypothalamic kisspeptin neurons, in the arcuate nucleus (ARC), has been less well characterized with respect to surge generation. Previous experiments have demonstrated ARC kisspeptin knockdown reduced the amplitude of LH surges, indicating that they have a role in surge amplification. The present study used an optogenetic approach to selectively stimulate ARC kisspeptin neurons and examine the effect on LH surges in mice with different hormonal administrations. LH level was monitored from 13:00 to 21:00 h, at 30-minute intervals. Intact Kiss-Cre female mice showed increased LH secretion during the stimulation period in addition to displaying a spontaneous LH surge around the time of lights off. In ovariectomized Kiss-Cre mice, optogenetic stimulation was followed by a surge-like secretion of LH immediately after the stimulation period. Ovariectomized Kiss-Cre mice with a low dose of 17β-estradiol (OVX+E) replacement displayed a surge-like increase in LH release during period of optic stimulation. No LH response to the optic stimulation was observed in OVX+E mice on the day of estradiol benzoate (EB) treatment (day 1). However, after administration of progesterone (day 2), all OVX+E+EB+P mice exhibited an LH surge during optic stimulation. A spontaneous LH surge also occurred in these mice at the expected time. Taken together, these results help to affirm the fact that ARC kisspeptin may have a novel amplificatory role in LH surge production, which is dependent on the gonadal steroid milieu.

CHANGES IN THE CONCENTRATIONS OF OESTRONE AND OESTRADIOL IN THE PERIPHERAL PLASMA OF THE DOMESTIC HEN DURING THE OVULATORY CYCLE

1974 ◽  
Vol 77 (3) ◽  
pp. 588-596 ◽  
Author(s):  
B. E. Senior
Keyword(s):  
Luteinizing Hormone ◽  
Laying Hens ◽  
Peak Level ◽  
Ovulatory Cycle ◽  
Blood Samples ◽  
Expected Time ◽  
Peripheral Plasma ◽  
Significant Change ◽  
Domestic Hen

ABSTRACT The concentrations of oestrone and oestradiol were measured by radioimmunoassay in the peripheral plasma of hens during the ovulatory cycle and of non-laying hens. During the ovulatory cycle when blood samples were taken at 4 or 6 h intervals for 24 h, the peak concentrations of oestrone and oestradiol occurred within the 6 h period immediately preceding ovulation. After the final ovulation of the clutch the oestradiol concentration fell gradually and did not rise again near the time when the last egg of the clutch was laid. There was no significant change in the concentration of oestradiol over a 24 h period in non-laying hens. When blood samples were taken at 2 h intervals during the 12–14 h period before the expected time of ovulation the oestradiol concentration rose 8 h before ovulation and reached a peak level 6–4 h beforehand. It is suggested that oestradiol may be involved in the mechanism stimulating the release of luteinizing hormone required for ovulation.

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