| 1. |
- Ahrén, K, et al.
(author)
-
Histamine stimulates progesterone synthesis and cyclic adenosine 3',5'-monophosphate accumulation in isolated preovulatory rat follicles
- 1987
-
In: Neuroendocrinology. - : S. Karger AG. - 0028-3835 .- 1423-0194. ; 46:1, s. 69-74
-
Journal article (peer-reviewed)abstract
- The effect of histamine on progesterone synthesis and cyclic adenosine 3',5'-monophosphate (cAMP) accumulation was studied in superfused and incubated follicles dissected free from immature rats treated with pregnant mare serum gonadotrophin (PMSG). Histamine, like LH, increased the progesterone synthesis, but to a smaller extent. The H2-antagonist, cimetidine, inhibited completely the histamine-induced progesterone increase while the H1-antagonist, pyrilamine, as well as propranolol and atropine did not affect the initial response but modified its duration. The specific H2-agonist, 4-methylhistamine, but not the H1-agonist, 2-methylhistamine, mimicked the effect of histamine on progesterone synthesis. In the presence of the phosphodiesterase inhibitor, IBMX, histamine increased tissue levels of cAMP. These results suggest that histamine stimulates progesterone synthesis via the H2-receptor with cAMP acting as secondary intracellular messenger.
|
|
| 2. |
- Kannisto, P, et al.
(author)
-
A heterogeneous population of alpha 1-adrenoceptors mediates contraction of the isolated follicle wall from the bovine ovary
- 1988
-
In: Acta Physiologica Scandinavica. - : Wiley. - 0001-6772 .- 1365-201X. ; 133:4, s. 563-571
-
Journal article (peer-reviewed)abstract
- Strips from Graafian follicles of bovine ovaries were tested for their contractile response in vitro in order to characterize the type of post-junctional alpha-adrenoceptor involved. Electrically induced contractions were inhibited concentration-dependently by the alpha 1-antagonist, prazosin. Besides noradrenaline the alpha 1-selective agonists, methoxamine and phenylephrine, caused the strips to contract, whereas the alpha 2-selective agonists clonidine, oxymetazoline and B-HT920 were without effect. However, the alpha 1-selective antagonist prazosin gave a line with a slope less than unity in the Schild plots with noradrenaline and methoxamine. From results obtained with or without the presence of two classes of neuronal uptake blockers (desipramine and cocaine) it is concluded that the post-junctional alpha 1-receptor population is inhomogeneous. The regular appearance of the Schild plot obtained with phenylephrine may be due to involvement also of a component of noradrenaline release by this agonist. The pA2 value in the test with phenylephrine was 9.27, with a corresponding kB of 3.81 +/- 1.15 X 10(-10) M.
|
|
| 3. |
- Kannisto, P, et al.
(author)
-
Characterization of presynaptic 5-HT receptors on adrenergic nerves supplying the bovine ovarian follicle
- 1987
-
In: British Journal of Pharmacology. - : Wiley. - 0007-1188. ; 92:3, s. 97-487
-
Journal article (peer-reviewed)abstract
- 1. The effects of 5-hydroxytryptamine (5-HT) on contraction and release of [3H]-noradrenaline were investigated in vitro in bovine ovarian follicle strips. Using available selective agonists and antagonists, an effort was made to characterize the type of receptor mediating the inhibitory effect of 5-HT on neurogenic contraction and release of [3H]-noradrenaline by electrical field stimulation. 2. 5-Hydroxytryptamine inhibited the neurogenic contraction and release of [3H]-noradrenaline evoked by electrical field stimulation in a concentration-dependent manner. Like 5-HT, 5-carboxamidotryptamine (5-CT) and methysergide reduced the transmitter release as well as the neurogenic contraction, whereas 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT) failed to inhibit both responses in concentrations up to 0.1 microM. 3. The 5-HT (1 microM)-induced inhibition of contractile responses was more evident during stimulation at low frequencies (4 and 8 Hz) than during high frequency electrical stimulation (16 and 32 Hz). 4. Methiothepin (1 microM) and methysergide (10 microM) significantly antagonized the inhibitory effect of 5-HT on the electrically evoked release of tritium, whereas cyanopindolol, MDL 72222 and ketanserin (all 0.1 microM) were without effect. In addition, ketanserin, MDL 72222, cimetidine, pyrilamine, atropine, propranolol and indomethacin were without effect on the 5-HT-induced inhibition of the neurogenic contraction. 5. It is suggested that 5-HT inhibits the electrically evoked transmitter release from adrenergic nerves in the bovine ovarian follicle wall via prejunctional 5-HT1-like receptors. This was based on the findings that 5-CT was a potent agonist, methiothepin an antagonist and the lack of effect of MDL 72222, cyanopindolol and ketanserin.
|
|
| 4. |
- Kannisto, P, et al.
(author)
-
Existence and coexistence of peptides in nerves of the mammalian ovary and oviduct demonstrated by immunocytochemistry
- 1986
-
In: Histochemistry. - : Springer Science and Business Media LLC. - 0301-5564 .- 1432-119X. ; 86:1, s. 25-34
-
Journal article (peer-reviewed)abstract
- The immunocytochemical distribution of substance P (SP), gastrin releasing peptide (GRP), vasoactive intestinal polypeptide (VIP), peptide histidine isoleucine (PHI), and neuropeptide Y (NPY) was studied in the ovary and the Fallopian tube (oviduct) of rats, guinea-pigs, cows, pigs and humans. Generally, the nerve supply was better developed in the oviduct than in the ovary. GRP fibers were most scarce in all tissues. Nerves containing SP were particularly numerous in the oviduct of rat and guinea-pig, supplying the muscular wall and blood vessels. VIP and PHI coexisted in dense plexuses of nerves, not only around blood vessels but also in the follicular wall and the interstitial gland of the ovary, as well as within the smooth muscle layers and subepithelially in the oviduct. The general distribution of NPY was similar, but these immunoreactive nerves were even more numerous. Sequential staining for dopamine-beta-hydroxylase and NPY together with results of chemical sympathectomy with 6-hydroxydopamine suggested that NPY was stored in the noradrenergic sympathetic nerves.
|
|
| 5. |
- Owman, C, et al.
(author)
-
Comparative histochemical distribution of nerve fibres storing noradrenaline and neuropeptide Y (NPY) in human ovary, fallopian tube, and uterus
- 1986
-
In: Medical Biology. - 0302-2137. ; 64:2-3, s. 57-65
-
Journal article (peer-reviewed)abstract
- Nerves containing noradrenaline were studied by formaldehyde-induced fluorescence and neuropeptide Y (NPY) was visualised by immunohistochemistry in the human ovary, Fallopian tube and uterus. All structures were richly supplied with noradrenergic fibres closely associated with the vascular and non-vascular smooth musculature. NPY-containing nerve terminals were consistently fewer, particularly in the ovary. The best developed nerve supply was found in the tubal isthmus and uterine cervix. Vessels were usually innervated by plexuses of nerves, containing NPY as well as noradrenaline. The discrepancy between the number of the two types of histochemically distinguishable nerves suggests that, if noradrenaline and NPY are co-localised in one and the same nerve, this is not a constant phenomenon in the human female reproductive tract.
|
|
| 6. |
- Schmidt, Gunther, et al.
(author)
-
Alteration by histamine of the sympathetic nerve-mediated contractions in the bovine ovarian follicle wall in vitro
- 1987
-
In: European Journal of Pharmacology. - : Elsevier BV. - 0014-2999. ; 135:1, s. 11-22
-
Journal article (peer-reviewed)abstract
- The histaminergic effect on electrically induced contractions and tritium release was studied in vitro, using strips from the wall of mature bovine ovarian follicles. Follicular fluid and blood plasma from the animals were analysed for electrolyte, bicarbonate, glucose and total protein concentrations in order to compare them with the concentrations of these components in the Krebs-Ringer solution used in the experiments. Electrical field stimulation (EFS) of the follicle strip caused a contraction which was completely blocked by tetrodotoxin and was predominantly of adrenergic origin since phentolamine, in contrast to atropine, blocked the response. The neurogenic response was inhibited by histamine in a concentration-dependent way via the H1-receptor since the H1-antagonist, pyrilamine, counteracted the inhibitory effect of histamine while the H2-antagonist, cimetidine, potentiated the effect. This histaminergic response of EFS-induced contractions could be reproduced in experiments where the H1-agonist, 2-methylhistamine, was inhibitory while the H2-agonist, 4-methylhistamine, had no obvious influence on the twitch response. Histamine reduced the contractile response to exogenous noradrenaline via the H1-receptor, because pyrilamine counteracted, and cimetidine potentiated the effect. The histamine-induced depression of the motor response to EFS and exogenous noradrenaline was probably due to a postjunctional effect mediated by the H1-receptor. Experiments utilizing [3H]noradrenaline release during EFS did not suggest prejunctional effects of histamine. Chemical determinations on follicle fluid and plasma showed that the artificial follicular fluid imitated well the environmental conditions the follicle wall is exposed to in situ.
|
|
| 7. |
- Schmidt, G, et al.
(author)
-
Cellular localization of ovarian histamine, its cyclic variations, and histaminergic effects on ovulation in the rat ovary perfused in vitro
- 1988
-
In: Journal of Reproduction & Fertility. - 0022-4251. ; 82:2, s. 409-417
-
Journal article (peer-reviewed)abstract
- Mast cells, visualized with toluidine blue staining and the Falck-Hillarp fluorescence technique, were mainly located around large blood vessels in the hilus region of the ovary in adult rats and in immature rats treated with PMSG. Histamine concentration in the rat ovary was significantly reduced after the LH surge in PMSG-treated animals, corresponding to a reduced number of ovarian mast cells. No marked change in the number of mast cells and histamine concentration was found in adult rats during the oestrous cycle. Histamine as well as the H1-agonist, 2-methylhistamine, and the H2-agonist, 4-methylhistamine, induced ovulations in the isolated perfused rat ovary. Ovulation rates were significantly lower than those evoked by LH. The histamine liberator, Compound 48/80, induced ovulations which were blocked by the combined effect of the H1- and H2-histamine receptor antagonists, cimetidine and pyrilamine. The anti-degranulating agent, disodium cromoglycate, did not block ovulations induced by Compound 48/80. The results show that the level of ovarian histamine, which is primarily stored in mast cells, can be influenced by PMSG treatment, and that the amine is able to induce ovulations in gonadotrophin-primed rats by an effect mediated by both H1 and H2 receptors.
|
|
| 8. |
- SCHMIDT, G., et al.
(author)
-
Is serotonin involved in the ovulatory process of the rat ovary perfused in vitro?
- 1988
-
In: Acta Physiologica Scandinavica. - : Wiley. - 0001-6772 .- 1365-201X. ; 132:2, s. 251-256
-
Journal article (peer-reviewed)abstract
- The presence of 5‐HT (serotonin) in ovarian tissue and its varying concentrations during the oestrous cycle suggests that it takes part in ovarian function and in the ovulatory process as one of several mediators of the inflammatory‐type reaction preceding follicular rupture. With the aid of a recirculating perfusion model, in which the central stimulatory action of 5‐HT was avoided, its direct ovarian effect on ovulation was studied using immature, pregnant, mare serum gonadotrophin (PMSG)‐treated rats. Four out of five ovaries ovulated after the addition of 5‐HT to the perfusion medium, though the ovulation rate (0.8 per ovary) did not reach the order of magnitude seen after luteinizing hormone (LH) stimulation (5.4 per ovary). The selective 5‐HT2 receptor antagonist, ketanserin, did not signficantly reduce the 5‐HT induced ovulations. The nonselective 5‐HT receptor antagonist, methysergide, blocked the 5‐HT induced ovulations, and moreover, reduced the LH‐stimulated ovulations. The calcium entry blocker, nifedipine, had no effect on either 5‐HT or LH induction ovulations.
|
|
| 9. |
- Sporrong, B, et al.
(author)
-
Histochemistry and ultrastructure of adrenergic and acetylcholinesterase-containing nerves supplying follicles and endocrine cells in the guinea-pig ovary
- 1985
-
In: Cell and Tissue Research. - : Springer Science and Business Media LLC. - 0302-766X .- 1432-0878. ; 240:3, s. 11-505
-
Journal article (peer-reviewed)abstract
- The autonomic nerve supply of the guinea-pig ovary was investigated by a combination of light- and electron microscopy. At the light-microscopic level, adrenergic fibres were identified due to their formaldehyde-induced fluorescence. In addition, the ovary contained acetylcholinesterase-positive fibres. In all parts of the ovary, the adrenergic fibres were most numerous. At the ultrastructural level it was possible to identify the adrenergic nerve terminals with the aid of the false adrenergic transmitter, 5-hydroxy-dopamine. Thus, large numbers of adrenergic terminals, characterized by their content of 50-60 nm, electron-dense synaptic vesicles, were seen within the interstitial gland, where they formed close contacts with the endocrine cells (membrane-to-membrane distance, 20-100 nm). The follicular theca externa was also richly supplied by adrenergic nerves. At this location, close contacts (50-100 nm) were identified between the nerve terminals and the smooth muscle-like cells. Very few adrenergic nerve fibres were present in the theca interna of follicles or in the corpus luteum. Non-adrenergic nerve terminals, characterized by electron-lucent synaptic vesicles of 50-60 nm diameter, were observed together with the adrenergic fibres. They were always present in much lower numbers than the latter. No "p-type" nerves were identified by electron microscopy.
|
|
