CONTROL OF SEBACEOUS GLAND FUNCTION IN THE RAT BY α-MELANOCYTE-STIMULATING HORMONE

SUMMARY The effect of α-MSH on sebum secretion and preputial gland weight was examined in intact, castrated and hypophysectomized male rats and in hypophysectomized rats receiving treatment with either testosterone propionate (TP) or progesterone. After treatment with α-MSHMSH for 2 weeks, increases in sebum secretion occurred in intact, castrated and hypophysectomized rats, but larger responses were found in the hypophysectomized rats that had received treatment with either TP or progesterone, suggesting that α-MSH acts synergistically with TP and progesterone to stimulate sebum secretion. α-Melanocyte-stimulating hormone also increased preputial gland weight in intact rats, but there was no response after castration and only a small response after hypophysectomy. However, when the hypophysectomized rats received simultaneous treatment with either TP or progesterone, α-MSH increased preputial gland weight. It is suggested that α-MSH acts directly on the sebaceous glands to stimulate lipogenesis and, together with steroid hormones, may have an important role in controlling sebaceous gland function in the rat and other hairy mammals. With the evolution of hair, certain of the MSH peptides may have lost their significance as pigmentary hormones and have developed a sebotrophic function. For this reason, it might be more appropriate to refer to these peptides as the 'sebotrophins'.

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EFFECT OF α-MELANOCYTE-STIMULATING HORMONE AND OVARIAN STEROIDS ON PREPUTIAL GLAND FUNCTION IN THE FEMALE RAT

Journal of Endocrinology ◽

10.1677/joe.0.0900053 ◽

1981 ◽

Vol 90 (1) ◽

pp. 53-58 ◽

Cited By ~ 10

Author(s):

S. M. DONOHOE ◽

A. J. THODY ◽

S. SHUSTER

Keyword(s):

Pituitary Hormones ◽

Female Rats ◽

Male Rats ◽

Female Rat ◽

Preputial Gland ◽

Melanocyte Stimulating Hormone ◽

Experienced Male ◽

Hypophysectomized Rats ◽

Gland Function ◽

Preputial Glands

Sexually experienced male rats were used to test the attractiveness of preputial gland odours of female rats. The male rats showed a clear preference for the preputial gland odours of hypophysectomized females given oestradiol benzoate (OB) for 3 or 8 days to those of control rats. Progesterone treatment had no effect on the attractiveness of the preputial gland odours of OB-treated hypophysectomized female rats. Administration of α-MSH for either 3 or 8 days, on the other hand, increased the attractiveness to male rats of preputial gland odours of OB-treated hypophysectomized females and the presence of progesterone produced no further change. When administered alone α-MSH had no effect on the attractiveness of the preputial gland odours. Other pituitary hormones, such as ACTH and prolactin, had no effect on the attractiveness of preputial gland odours of OB-treated hypophysectomized rats when administered for 3[unk]days. An increase in preputial gland size was only seen when OB, progesterone and α-MSH were administered together. It would appear that no relationship exists between the size of the preputial glands and their ability to attract male rats. It is concluded that, while α-MSH and progesterone may be important in controlling growth of the preputial glands, an interaction between α-MSH and oestrogen is more important for regulating the production of sex attractants by the preputial glands.

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THE INFLUENCE OF THE PITUITARY ON THE RESPONSE OF THE SEBACEOUS AND PREPUTIAL GLANDS OF THE RAT TO PROGESTERONE

Journal of Endocrinology ◽

10.1677/joe.0.0450257 ◽

1969 ◽

Vol 45 (2) ◽

pp. 257-263 ◽

Cited By ~ 15

Author(s):

F. J. EBLING ◽

ERIKA EBLING ◽

J. SKINNER

Keyword(s):

Growth Hormone ◽

Sebaceous Gland ◽

Male Rats ◽

Preputial Gland ◽

Sebaceous Glands ◽

Gland Weight ◽

Hypophysectomized Rats ◽

Sebum Production ◽

Preputial Glands

SUMMARY Progesterone, given as an implant releasing 0·1–0·2 mg./day for 24 days, failed to increase sebum production or preputial gland weight in castrated or hypophysectomized-castrated male rats. A dose of 10 mg./day in arachis oil also failed to increase sebum production or mitoses in the sebaceous glands, though it increased by 70% preputial gland weight in the presence of the pituitary. Hypophysectomy greatly reduced preputial gland wt, and the response of hypophysectomized rats to 10mg. progesterone/day was much less than when the pituitary was present. A porcine growth hormone preparation, known to facilitate the response of the sebaceous gland to testosterone in the hypophysectomized rat, failed to facilitate the response of the preputial gland to progesterone. It is concluded that 'sebum-permissive' activity (the facilitation of the response of the sebaceous gland to testosterone) may be distinct from ' sebotropic' activity (facilitation of the response of the preputial gland to progesterone), and it is argued that each of these activities may prove to be separable from somatotrophic activity.

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THE EFFECT OF HYPOPHYSECTOMY ON THE RESPONSE OF THE SEBACEOUS GLAND TO TESTOSTERONE PROPIONATE

Journal of Endocrinology ◽

10.1677/joe.0.0490329 ◽

1971 ◽

Vol 49 (2) ◽

pp. 329-333 ◽

Cited By ~ 12

Author(s):

A. J. THODY ◽

S. SHUSTER

Keyword(s):

Sebaceous Gland ◽

Testosterone Propionate ◽

Preputial Gland ◽

Sebaceous Glands ◽

Gland Weight ◽

Actual Increase ◽

Small Doses ◽

Sebum Secretion ◽

Higher Doses

SUMMARY The effect of varying doses of testosterone propionate (TP) on the sebum secretion and preputial gland weight of castrated and hypophysectomized—castrated rats was studied. The changes in preputial gland weight closely paralleled those of sebum secretion. Small doses of TP (0·05 mg) stimulated sebum secretion in hypophysectomized-castrated rats, but not in the castrated rats. Higher doses of TP increased sebum secretion in both the hypophysectomized—castrates and the castrated rats. While 0·5 mg TP completely restored sebum secretion to normal levels in castrated rats but not in the hypophysectomized—castrated rats, the actual increase in sebum secretion produced by this dose of TP was similar in both groups. It is concluded that at physiological doses the action of TP on the sebaceous glands is independent of the pituitary. However, the presence of the pituitary is required for normal sebaceous gland activity.

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THE EFFECTS OF HYPOPHYSECTOMY AND TESTOSTERONE ON THE ACTIVITY OF THE SEBACEOUS GLANDS OF CASTRATED RATS

Journal of Endocrinology ◽

10.1677/joe.0.0470219 ◽

1970 ◽

Vol 47 (2) ◽

pp. 219-224 ◽

Cited By ~ 19

Author(s):

A. J. THODY ◽

S. SHUSTER

Keyword(s):

Adult Male ◽

Testosterone Propionate ◽

Male Rats ◽

Preputial Gland ◽

Sebaceous Glands ◽

Gland Weight ◽

Preputial Glands ◽

Sebum Secretion ◽

Intact Rats

SUMMARY Adult male rats which had been castrated prepuberally secreted less sebum than intact rats. When hypophysectomy followed castration there was a further decrease in sebum secretion. Treatment of the castrated and hypophysectomized castrated rats with testosterone propionate produced a large and comparable increase in the sebum secretion of both groups. Testosterone propionate also caused a marked increase in the preputial gland weight of the castrated rats, although a much smaller response occurred after hypophysectomy. The effect of hypophysectomy on the response of the sebaceous and preputial glands to testosterone is discussed.

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EFFECT OF α-MELANOCYTE-STIMULATING HORMONE AND TESTOSTERONE ON CUTANEOUS AND MODIFIED SEBACEOUS GLANDS IN THE RAT

Journal of Endocrinology ◽

10.1677/joe.0.0710279 ◽

1976 ◽

Vol 71 (3) ◽

pp. 279-288 ◽

Cited By ~ 50

Author(s):

A. J. THODY ◽

MARY F. COOPER ◽

P. E. BOWDEN ◽

D. MEDDIS ◽

S. SHUSTER

Keyword(s):

Sebaceous Gland ◽

Cellular Proliferation ◽

Testosterone Propionate ◽

Wax Ester ◽

Preputial Gland ◽

Sebaceous Glands ◽

Gland Size ◽

Gland Volume ◽

Gland Weight ◽

Sebum Secretion

SUMMARY The effects of α-MSH and testosterone propionate on sebum secretion, sebaceous gland volume, dermal lipogenesis, and preputial gland weight and lipogenesis were examined in hypophysectomized rats. Hypophysectomy reduced sebum secretion, sebaceous and preputial gland size, and dermal and preputial gland lipogenesis. The greatest effects were seen on the biosynthesis of wax esters and squalene. Testosterone propionate (TP) increased sebum secretion, sebaceous gland volume and preputial gland weight and lipogenic activity, but had no significant effect on the pattern of lipid labelling. α-MSH had no effect on sebaceous or preputial gland size, but increased sebum secretion and dermal lipogenesis, especially wax ester biosynthesis. When given together TP and α-MSH had a synergistic effect on sebum secretion and on dermal and preputial gland lipogenesis, and the pattern of lipid labelling was shifted towards normal. TP and α-MSH also showed synergism in increasing preputial gland weight, but together they had no greater effect on sebaceous gland volume than that achieved with TP alone. These results suggest that TP and α-MSH have different actions on the sebaceous glands with α-MSH acting predominantly on lipogenesis and TP on cellular proliferation and turnover leading to an increase in gland size. Preputial glands differ from cutaneous sebaceous glands in their response to α-MSH and androgen which could be a reflection of their more specialized function.

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Mechanism of action of α-melanocyte-stimulating hormone in rat preputial glands: the role of androgen metabolism

Journal of Endocrinology ◽

10.1677/joe.0.0940289 ◽

1982 ◽

Vol 94 (2) ◽

pp. 289-294 ◽

Cited By ~ 3

Author(s):

J. B. Hay ◽

D. Meddis ◽

A. J. Thody ◽

S. Shuster

Keyword(s):

Reductase Activity ◽

Hydroxysteroid Dehydrogenase ◽

Preputial Gland ◽

Melanocyte Stimulating Hormone ◽

Hypophysectomized Rats ◽

Total Lack ◽

Preputial Glands ◽

And Control ◽

Stimulating Hormone

The metabolism of testosterone and 5α-dihydrotestosterone has been studied in vitro in preputial glands of posterior hypophysectomized, totally hypophysectomized and control sham-operated rats. The level of C19 steroid 5α-reductase activity/unit of preputial gland DNA did not fall after removal of the neurointermediate lobe and rose after total hypophysectomy. It was concluded from this that the androgen unresponsiveness of the preputial glands of hypophysectomized rats was not due to a near-total lack of 5α-reductase and hence that the combined synergistic action of testosterone and α-melanocyte-stimulating hormone (α-MSH) on preputial gland activity was unlikely to be due to an α-MSH-mediated restoration of 5α-reductase levels in hypophysectomized rats. Levels of 3α-and 3β-hydroxysteroid dehydrogenase but not of 17β-hydroxysteroid dehydrogenase appeared to be altered by hypophysectomy.

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General activity in intact and hypophysectomized rats after administration of melanocyte-stimulating hormone (MSH), melatonin, and Pro-Leu-Gly-NH2

Physiology & Behavior ◽

10.1016/0031-9384(73)90330-2 ◽

1973 ◽

Vol 10 (2) ◽

pp. 399-401 ◽

Cited By ~ 55

Author(s):

Abba J. Kastin ◽

M. Clinton Miller ◽

Lorraine Ferrell ◽

Andrew V. Schally

Keyword(s):

General Activity ◽

Melanocyte Stimulating Hormone ◽

Hypophysectomized Rats ◽

Stimulating Hormone

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EFFECTS OF FOLLICLE-STIMULATING HORMONE AND LUTEINIZING HORMONE ON PLASMA TESTOSTERONE LEVELS IN HYPOPHYSECTOMIZED AND IN INTACT IMMATURE AND ADULT MALE RATS

Journal of Endocrinology ◽

10.1677/joe.0.0610193 ◽

1974 ◽

Vol 61 (2) ◽

pp. 193-198 ◽

Cited By ~ 14

Author(s):

S. EL SAFOURY ◽

A. BARTKE

Keyword(s):

Luteinizing Hormone ◽

Adult Male ◽

Follicle Stimulating Hormone ◽

Seminal Vesicles ◽

Male Rats ◽

Plasma Testosterone ◽

Adult Rats ◽

Testosterone Levels ◽

Hypophysectomized Rats ◽

Stimulating Hormone

SUMMARY The effects of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) on plasma testosterone levels were examined in hypophysectomized and in intact immature and adult male rats. The animals were injected with saline, LH, FSH, or both gonadotrophins twice daily for 3·5 days and were killed 3 h after the last injection. Plasma testosterone levels were measured by radioimmunoassay. In immature hypophysectomized rats, plasma testosterone levels were not changed by treatment with LH, FSH or LH plus FSH. The weight of the testes and of the seminal vesicles was increased only in animals injected with both LH and FSH. In adult hypophysectomized rats, LH caused the expected increase in plasma testosterone levels, while FSH injected alone had no effect. Plasma testosterone levels in rats treated with 5 μg LH and 20 μg FSH were significantly greater than those in animals given 5 μg LH alone. However, the same dose of FSH did not potentiate the action of 25 μg LH on plasma testosterone levels. In adult hypophysectomized rats the weight of testes was not affected by any of the treatments. The weight of the seminal vesicles was increased by the higher dose of LH and addition of FSH caused no further increase. In intact immature and adult rats plasma testosterone levels and the weight of testes were not changed by any of the treatments. Seminal vesicle weight was increased only in adult rats treated with the higher dose of LH together with FSH. The results demonstrate that FSH potentiates the action of low doses of LH on plasma testosterone levels in adult hypophysectomized rats and suggest that FSH may be involved in the regulation of androgen secretion by the rat testis.

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