Collagenase-dispersed carp pituitary cells in a perifusion system were used to study the role of calcium ions in the mechanism of GnRH action on the release of maturational gonadotropin (GtH) in fish. The specific calcium chelator EGTA and the calcium antagonist manganese (Mn2+) caused a 40% inhibition in the basal GtH release and completely blocked GnRH-stimulated GtH release. Short-term appli...

Vitellogenic stage carp ovaries were collected aseptically and the cells of ovarian follicles were dispersed by trypsin treatment and cultivated as monolayer. Control cultures were grown in medium M199 alone. Media for experimental cultures were supplemented either with 100 µl ml-1 of CPH and CPS-carp GnRH (cultivated pituitary cell secretion affected by 10-6, 10-8, 10-10 M carp GnRH). The dire...

Vitellogenic stage carp ovaries were collected aseptically and the cells of ovarian follicles were dispersed by trypsin treatment and cultivated as monolayer. Control cultures were grown in medium M199 alone. Media for experimental cultures were supplemented either with 100 µl ml-1 of CPH and CPS-carp GnRH (cultivated pituitary cell secretion affected by 10-6, 10-8, 10-10 M carp GnRH)....

The aim of the experiments was to evaluate the influence of human kisspeptin on LH secretion of Prussian carp (Carassius gibelio) females during ovarian recrudescence and spawning season. For the experiments, human kisspeptin KISS1 (0.1 mg kg(-1) of body weight--b.w.), GnRH analogue (Des Gly(10), D-Ala(6)) GnRH-A (20 µg kg(-1) b.w.) and dopamine antagonist (pimozide) (5 mg kg(-1) b.w.) were use...

Corespondență: Dr. Andreea Carp Velișcu e-mail: andreea_veliscu@ yahoo.com Introduction. The luteal phase in IVF stimulated cycles is very different from that in natural cycles, so is very important to mimic the perfect condition for pregnancy. Method. Since January 2015 until December 2015, we have 88 cycles in which the triggering was done with GnRH agonist. We performed an embriotransfer in ...

The involvement of different types of voltage-dependent calcium channels (VDCC) in the stimulatory action of GnRH (in comparison with K+) on maturational gonadotropin (GtH) release was investigated using superfused carp pituitary cells. The action of these 2 stimulants was not modified either by D600 or nifedipine (drugs blocking L-type of VDCC). Cadmium (Cd2+), which blocks all types of VDCC i...

The goldfish, a member of the carp family, is a widely used model for reproductive neuroendocrine studies of economically important fish. The two gonadotrophin (GTH) molecules released from the fish anterior pituitary, GTH-I and GTH-II, are structurally similar to tetrapod FSH and LH, respectively. Gonadotrophin II is the best studied, and in goldfish stimulates gonadal growth and steroidogenes...

The effects of naltrexone on the in vitro luteinizing hormone (LH) secretion from whole pituitary glands as well as from dispersed pituitary cells of common carp (Cyprinus carpio L.) in primary cell culture were studied. The perifusion of whole pituitary glands with naltrexone at a concentration of 10 M caused a significant increase of LH secretion compared to the control. This finding suggests...

The secretion of gonadotropins (GtH) in goldfish and carp, is stimulated by GtH-releasing hormone (GnRH) and is inhibited by dopamine. Studies with antidopaminergics have demonstrated to be effective in order to stimulate the spermiation and the ovulation in different species of teleosts. The reserpine, a drug that deplets the dopamine, has shown to stimulate the spermiation in the common carp....