Results 271 to 280 of about 24,051 (299)

The gonad morphology and maturation in Arctic Calanus species

Journal of Marine Systems, 1998
Gonad morphology and maturation of the dominant Arctic copepod species Calanus glacialis and C. hyperboreus were studied using a combination of observations on whole animals (“whole-body analysis”) and histological sections to describe basic reproductive processes. The comparison with C.
openaire   +3 more sources

Effect of amygaloid lesions on gonadal maturation in male and female ferrets

American Journal of Physiology-Legacy Content, 1975
Two experiments were performed to determine whether the amygdala is involved in theregulation of gonadal maturation in the ferret. In an experiment with prepuberal males it was found that testicular and epididymal wieghts, seminiferous tubule diameters, Leydid cell number, and ratings of spermatogenic development were the samein animals autopsied 4 wk
M J, Baum, D A, Goldfoot
openaire   +2 more sources

The endocrine regulation of gametogenesis and gonad maturation in fishes

General and Comparative Endocrinology, 1972
Abstract The gonads of fishes, like those of all other vertebrates, contain germinal and endocrine tissue, and both components require the support of hormones if they are to develop and function normally. The steroid-secreting tissues invariably need hormonal stimulation but the situation relating to gametogenesis is more variable.
openaire   +1 more source

Influence of melatonin on gonad maturation inLineus lacteus (Heteronemertini, Lineidae)

The Journal of Experimental Zoology, 1996
The annual reproductive cycle of Lineus lacteus is regulated by photoperiod and thermoperiod. Gonad maturation depends on a gonad-inhibiting hormone (GIH) secreted by the cerebral ganglia, in which melatonin was also observed. Results in the worm showed that melatonin concentrations seemed to vary at the two most appropriate times of the year (spawning
Fabrice Arnoult, Guy Vernet
openaire   +1 more source

Functional maturation of the pituitary-gonadal axis in the neonatal female rat

Biology of Reproduction, 1995
The development onset of the pituitary feedback response to LH/hCG-stimulated ovarian activity was studied in the neonatal rat. A single injection of hCG (600 IU/kg BW) was administered to groups of rats between 1 and 10 days of age, and the responses, i.e., ovarian estradiol (E2), progesterone (P), and testosterone (T) production as well as serum LH ...
T A, Sokka, I T, Huhtaniemi
openaire   +2 more sources

The brain-pituitary-gonadal axis in the rainbow trout, Salmo gairdneri: Gonadal hormones and the maturation of gonadotropic cells

Cell and Tissue Research, 1982
Intact and castrated juvenile male rainbow trout (Salmo gairdneri) were treated with testosterone and gonadotropic hormone (GTH) to determine the maturational effects of these hormones on the GTH-cells. Electron-microscopic studies of the GTH-cells revealed that GTH and testosterone in intact animals, and testosterone in castrated fish, caused GTH-cell
J T, Gielen, H J, Goos, J, Peute, R A, van den Bosch, P G, van Oordt   +4 more
openaire   +2 more sources

[The role of the gonads in the maturation of corticotropic function in rats].

Comptes rendus hebdomadaires des seances de l'Academie des sciences. Serie D: Sciences naturelles, 1975
The rates of pituitary and adrenals growth, in male and female Rats, are reversed at puberty. It seems that the stress induced plasma corticosterone increase is inhibited by testis before puberty and stimulated by ovarian after puberty.
J, Maniey, G, Lescoat, J, Lanoe, P, Rochcongar, A M, Drouet   +4 more
openaire   +1 more source

Gonadal sex differentiation in Eleutheronema tetradactylum: Histological features and transcriptomic insights from mature gonads

Comparative Biochemistry and Physiology Part D: Genomics and Proteomics
Plasticity in teleosts is a fascinating evolutionary strategy enables species to acclimate to environmental changes. However, the molecular mechanisms that underlie gonadal differentiation and reversal remain incompletely understood. The four-finger threadfin (Eleutheronema tetradactylum), a protandrous hermaphrodite belonging to the Polynemidae family,
Evodia Moses, Mkulo, Lukman, Iddrisu, Salifu, Ibrahim, Jiansheng, Huang, Linjuan, Wang, Anna, Zheng, Happiness Moses, Mwemi, Jin, Minxuan, Huijuan, Zhang, Baogui, Tang, Qian, Ma, Kwaku, Amoah, Bei, Wang, Zhongliang, Wang   +13 more
openaire   +2 more sources

Artificial Induction of Conditioning (Gonad Maturation)

2021
openaire   +1 more source

Patterns of maturation, gonad maturity gradation and cycle of maturation of Pacific cod (Gadus macrocephalus)

The researches of the aquatic biological resources of Kamchatka and of the north-west part of the Pacific Ocean, 2016
Nadezhda P. Sergeeva, Alexander I. Varkentin   +1 more
openaire   +1 more source