Immunization of female rabbits against testosterone stimulates testosterone accumulation by isolated ovarian follicles

Ovarian follicles isolated from female rabbits after active immunization against testosterone-3-oxime bovine serum albumin produced more testosterone than similar follicles from controls.     

Alloxan-induced hyperglycemia increases progestin and androgen accumulation by isolated rabbit follicles in vitro

Follicles isolated from Alloxan-treated rabbits and incubated in vitro, accumulated more progesterone and testosterone than those from saline-treated rabbits. LH augmented the accumulation of these 2 steroids. By contrast, the estradiol response to LH stimulation by follicles from Alloxan-induced hyperglycemic rabbits was diminished when compared to follicles from saline-treated rabbits. Ovaries from hyperglycemic rabbits also appeared to have more cystic follicles.     

Alloxan-induced hyperglycemia increases progestin and androgen accumulation by isolated rabbit follicles in vitro

Summary Follicles isolated from Alloxan-treated rabbits and incubated in vitro, accumulated more progesterone and testosterone than those from saline-treated rabbits. LH augmented the accumulation of these 2 steroids. By contrast, the estradiol response to LH stimulation by follicles from Alloxan-induced hyperglycemic rabbits was diminished when compared to follicles from saline-treated rabbits. Ovaries from hyperglycemic rabbits also appeared to have more cystic follicles.This work was supported by the Medical Research Council of Canada. The technical assistance of Misses P. Dimond and J. Osoko is gratefully acknowledged. Dr B.R. Bhavnani provided the stimulus for this study.     

Apoptosis occurs in granulosa cells but not cumulus cells in the atretic antral follicles in pig ovaries

The porcine antral follicles, 3–6 mm in diameter, were dissected from the ovaries of mature pigs, and then granulosa and cumulus cells were isolated from each follicle. In atretic follicles, high activity of neutral Ca²⁺/Mg²⁺-dependent endonuclease and DNA ladder formation, estimated by electrophoresis, were noted in granulosa cells but not in cumulus cells. Extremely low activity of the endonuclease and no DNA ladder formation were observed in both types of cells obtained from healthy follicles. Moreover, apoptotic cells were observed histochemically among granulosa cells only. A good correlation (r=0.987) between the endonuclease activity of granulosa cells and the progesterone/estradiol ratio of follicular fluid in each follicle was found. These results suggest that apoptosis occurs in granulosa cells but not cumulus cells in the atretic antral follicles in pigs.     

Neogenesis of functional hair follicles in adult mouse skin selectively induced by tumour-promoting phorbol esters

Neogenesis of functional hair follicles in the tail skin of adult mice can quantitatively be demonstrated after long-term treatment with tumour-promoting phorbol esters. The ability to induce the formation of new hair follicles correlates with the hyperplasiogenic and tumour-promoting capacity of the phorbol esters. Hyperplasiogenic but nonpromoting phorbol esters do not lead to the formation of new hair follicles.     

Autoradiographic analysis of FSH binding during follicular atresia

Binding of FSH to ovarian cells was studied in PMSG primed immature Swiss mice, 48 h after PMSG treatment, FSH-binding was higher in the periphery than in the cumulus cells of the antral follicles. Binding of FSH to granulosa cells of normal follicles was observed to be specific, 48 h after PMSG injection. No localization in the atretic follicles could be seen by autoradiography 72 h after priming.     

Neogenesis of functional hair follicles in adult mouse skin selectively induced by tumour-promoting phorbol esters

Summary Neogenesis of functional hair follicles in the tail skin of adult mice can quantitatively be demonstrated after long-term treatment with tumour-promoting phorbol esters. The ability to induce the formation of new hair follicles correlates with the hyperplasiogenic and tumour-promoting capacity of the phorbol esters. Hyperplasiogenic but nonpromoting phorbol esters do not lead to the formation of new hair follicles.Acknowledgment. I am grateful to Dr K. Goerttler and Dr F. Marks for helpful advice and discussions.     

A new technique for dissociation of hair follicles into single cells

Summary A method is described for the complete dissociation of mouse hair follicles into a suspension of single cells suitable for cell culture. Dermal tissue containing hair follicles is digested sequentially with trypsin and chondroitinase ABC under mild conditions.     

A new technique for dissociation of hair follicles into single cells.

A method is described for the complete dissociation of mouse hair follicles into a suspension of single cells suitable for cell culture. Dermal tissue containing hair follicles is digested sequentially with trypsin and chondroitinase ABC under mild conditions.     

Morphogenesis and hormonogenesis in vitro of granulosa cells of the European badger Meles meles L.]

Granulosa cells harvested from follicles of Badger during inactive luteal phaseluteinize in vitro. The results demonstrate that the serum's origin influence progesteron production of Badger's granulosa cells in culture. LH appears equally to be stimulating.     

Über die morphologischen Veränderungen am menschlichen Ovar unter Einwirkung eines hormonalen Antikonzeptivums

Summary Under the effect of Anovlar®, which had been administered during two cycles, one Corpus luteum per cycle developed; characteristic of each was the thecahypoplasia. The typical epitheloid Theca interna cells were lacking in the Theca interna of the existing vesicular follicles. Theca interna growth in the atretic vesicular follicles could not be demonstrated.     

alpha-globulin follicular fluid proteins within small and large bovine follicles.

Fluids from small (FF-S) and large (FF-L) bovine ovarian follicles were observed electrophoretically for differences in the alpha-globulin protein profile. FF-L possessed a fast migrating alpha-globulin 3 and a greater percentage of FF-L samples contained a higher number of alpha-globulin bands.     

Genetics of early mammalian folliculogenesis

Early ovarian folliculogenesis begins with the breakdown of germ cell clusters and formation of primordial follicles. Primordial follicles are the smallest ovarian follicle units continuously recruited to grow into primary and more advanced ovarian follicles. Genes expressed in the germ cells such as Figla, Nobox, Kit and Ntrk2, as well as genes expressed in the surrounding somatic cells such as Foxl2, Kitl and Ngf, play critical functions during early folliculogenesis. Transgenic mice continue to provide important insights into the genetic pathways that regulate early mammalian folliculogenesis. Genes critical in early folliculogenesis are important determinants of reproductive life span and represent candidate genes for human ovarian failure. Received 25 August 2005; received after revision 18 October 2005; accepted 21 November 2005     

Effect of actinomycin D or puromycin on microsomal testosterone hydroxylase activity enhanced by testosterone in female rat liver

Summary The injection of testosterone propionate for 4 successive days into female rats resulted in an increase of the in vitro conversion of the hydroxylated testosterones from testosterone by the hepatic microsomal, fraction, but no change in the content of microsomal cytochrome P-450 occurred. Actinomycin D or puromycin, which was administered for 4 days with injections of testosterone propionate, prevented the enzyme induction.     

Studies on the thyroid in transgenic mice expressing the genes for human and bovine growth hormone

The thyroid glands of transgenic mice (TM) expressing the genes for human (h) and bovine (b) growth hormone (GH) were studied. The percentages of larger follicles in hGH TM of either sex were significantly greater than in the corresponding normal littermates, and follicles ranging up to 350 microns in diameter were present in male hGH TM. In contrast, thyroid follicles were only slightly enlarged in male bGH TM, and were unchanged in female bGH TM. The serum concentrations of T4 were significantly decreased in male bGH TM and not altered in the other groups. Serum concentrations of T3 were slightly, but significantly increased in female hGH TM and female bGH TM, but were unaffected in male TM of either type. Since the principal difference between these foreign GHs in rodents is the additional lactogenic activity of human GH, these results may indicate that the effects of prolactin can influence the development of the thyroid.     

Dendritic reticulum cells in AIDS-related lymphadenopathy

Summary One of two cases of acquired immune deficiency syndrome-related persistent generalized lymphadenopathy revealed a profoundly altered pattern of dendritic reticulum cells as demonstrated by immunoreactive acid cysteine proteinase inhibitor. The alterations could be related to totally or partially destructed lymphoid secondary follicles.Acknowledgments. This work has been partially supported by the grant from the Sigrid Juselius Foundation, Finland.     

Do luteinized unruptured follicles secrete progesterone in mature female rats

Unruptured luteinized follicles were shown to secrete less progesterone than did postovulatory corpora lutea in cyclic female rats.     

Follicles development in the foetal human ovary.

In the foetal human ovary, diameters of oocyte and follicle, as well as those of oocyte and nucleus, are found to be positively and linearly correlated with each other. Follicle diameter and number of granulosa cells also show a positive and linear relationship. Finally, in all ovaries examined, from 5 months after conception onwards, small antral follicles were assessed.     

Central aromatization of testosterone in testicular feminized mice

Summary Aromatization of testosterone was examined in hypothalamic and cerebral cortex tissues from 32 mice-10 normal males, 10 normal females, 2 carrying the testicular feminized gene (Tfm) and 10 Tfm with the modifying (o^hv) gene. Total aromatization was 1.5 times greater in normal males than females. In both forms of Tfm, conversions were equal and similar to normal females.This work was supported by the Medical Research Council of Canada.     

Nerves and muscles regulating feather follicle movements in the chicken

Summary It was found that most feather follicles possess more than a single muscle system but only single nerve endings were observed in a feather follicle. It seems that muscles exist which antagonize each other. Anastomoses of nerves orginating from different sources and flowing of mixed nerves into the feather follicle could explain the antagonistic action of the muscles on the feather follicle.Partially supported by a grant from the Israel Egg and Poultry Board.