Synthetic releasing hormones LH/FSH-RH and LH-RH : effect of intracerebral and intramuscular injections on female carp (Cyprinus carpio L.) maturation

Abstract

Summary. The Introduction.

Profiles of plasma gonadotropin and 17β-estradiol in the common carp, Cyprinus carpio L., as related to spawning induced by hypophysation or LH-RH treatment

“…The levels of exogenous c-GTH found after « hypophysation » were in the same range as those reported in other similar experiments (Jalabert et a/., 1977 ;Fostier, Breton and Jalabert, 1979 ;Bieniarz et al,1980 (Sokolowska et at., 1978), using doses of the same order (1 mg/kg/day for 9 days), also obtained more rapid oocyte maturation but not ovulation. Giving doses 600 to 1 500 times higher than ours induced ovulation in the ayu (Hirose and Hishida, 1974), the goldfish (Lam et al, 1975(Lam et al, , 1976, different species of carp (Conference on Application of Hormones to economic Fish, 1975), the Japanese medaka (Chan, 1977), the plaice and the goby (Aida et al, 1978).…”

“…The most empirically efficient procedure is to give two injections, the first containing 10 p. 100 of the total dose and the second 90 p. 100 (Antalfi and T61 9 , 1975). This classical so-called « hypophysation » has been tentatively replaced by LH-RH injections which induce ovarian maturation (Sokolowska, Popek and Bieniarz, 1978), or even ovulation (Conference on Application of Hormones to Economic Fish, 1975), in carp and ovulation in the ayu (Hirose and lshida, 1974), goldfish (Lam et al, 1975(Lam et al, , 1976, plaice and goby (Aida et al, 1978 Weil, 1973 ;Weil, Breton and Reinaud, 1975 ;Crim, Peter and Billard, 1976) and salmonids (Crim and Cluett, 1974 ;Weil et al, 1978). Exogenous gonadotropin injections increase estradiol production during vitellogenesis in trout and at the end of the cycle in carp (Fostier, Breton and Jalabert, 1979), but at that final stage in trout, Van Bohemen and Lambert (1979) did not detect aromatization enzymes in the ovary.…”

The effect of luteinizing hormone-releasing hormone analogue (LHRHa) in combination with different drugs with anti-dopamine and anti-serotonin properties on gonadotropin release and ovulation in the African catfish, Clarias gariepinus

“…Induction of oocyte maturation and/or ovulation has been reported in the carp (Sokolowska et al, 1978;Weil et al, 1980); goldfish (Lam et al, 1975) ; plaice, Pleuronectes platessa, and goby, Acanthogobius flavimanus (Aida et al, 1978;ayu, Plecoglossus altivelis (Hirose and Ishida, 1974) ; rainbow trout, Salmo gairdneri (Crim et al, 1983) ; and coho salmon, Oncorhynchus kisutch (Donaldson et al, 1981;Van Der Kraak et al, 1983 ) . On the other hand, in goldfish, single or multiple injections of LHRH or its analogues in different doses and regimes could not induce a very high rate of ovulation Sokolowska et al, 1984).…”

Serum gonadotropin levels in mature male goldfish in response to luteinizing hormone – releasing hormone (LH-RH) and des-Gly10-[D-Ala6]-LH-RH ethylamide

“…, and multiple injections of LH-RH over several days were required for oocyte maturation (Sokolowska et al 1978) and ovulation (Lam et al 1975;Lam et al 1976) in some cases. However, studies on the time course of changes in blood gonadotropin (GtH) indicate that peak levels are usually within 1 h or less after injection of LH-RH or a superactive analogue (Breton and Weil 1973; Crim and Cluett 1974;Fish Reproductive Physiology Research Group and Peptide Hormone Group 1978).…”

“…Synthetic luteinizing hormone -releasing hormone (LH-RH) and certain of its superactive analogues have been used to induce oocyte development (Chan 1977), oocyte maturation (Sokolowska et al 1978), and ovulation (Hirose and Ishida 1974;Lam et al 1975;Lam et al 1976 …”