13.5 Effects of Gonadal Hormones on Adults Flashcards
what clearly demonstrates he role of gonadal hormones in male sexual behaviour
orchidectomy
what are the two main conclusions from the Bremer study on orchidectomized males?
- reduces sexual interest and behaviour
2. rate and degree of loss are variable
what are the main outcomes of orchidectomy on sexual behaviours (4)
- about half of cases will become asexual within a few weeks
- others can lose their ability to get hard but still have sexual interest and pleasure
- some can still cpulate, but less enthusiastically
- body changes included reduction of body hair on torso, limbs, face, deposition of fat on hips and chest, softening of the skin, reduced muscle mass
how many out of the 102 orchidectomized sex offenders reengaged in sex crimes?
3
why do some males remain sexually active following orchidectomy?
adrenal androgens may play some role - non direct evidence for this tho
what confirms the assumption that the main effects of orchidectomy are associated with the loss of T?
replacement injections of T
describe the case of the man who lost and regained his manhood
castrated in war, soft body w little muscle, wider hips and narrower shoulders, impotent
- T injections
- after 5, and rapid and prolonged erections
after 12 weeks, gained 18 pounds of muscle
- didn’t eliminate his sterility
what are the two widespread assumptions that follow from the necessity of T in male sexual behaviours
are they correct?
- level of a mans sexuality is related to his T levels in blood
- mans sex drive can be increased by increasing levels of T
- NOPE, unrelated in both cases
explain the Grunt and Young experiments on sexual behaviour inn response to T
- rated sexual behaviour of the male guinea pigs in the study
- based on the ratings, grouped them into low, medium, high
- castration, all sex drives fell to negligible within weeks
- recovered after initiation of T replacement
- even tho they all received the same amount, they returned to their old level of sexuality
what is Dihydrotestosterone and why is it interesting
- non aromatizable androgenn
- restores copulatory behaviour in castrated male primates, not in rodents
- indicates that restoration of copulatory behaviour by T has different mechanisms in rodents and primates
- directly due to T in primates
- due to aromatized estradiol in rodents
How long are the gonadal hormone cycles of mature female rats and guinea pigs
describe
4 days
- gradual increase ion estrogen secretion by developing follicles in the 2 days before ovulation
- sudden surge in progesterone as the egg is release
- initiate estrus (12-18 hours when the female is fertile, receptive, proceptive and sexually attractive
what does the close relation between the hormone cycle and estrous cycle indicate about sexual behaviour in female rats and guinea pigs
under the control of hormonal control since sex behaviours match up so well with gonadal hormones
Do the effects of ovariectomy confirm or refute the position that female rodent estrus cycles are determined by gonadal hormone cycles?
- How? (2)
confirms
- ovariectomy produces decline in both receptive and proceptive behaviours
- estrus can be induced in castrated females if you inject estradiol and then progesterone and day and a half later
how are female primates different from rodent and other mammals in terms of the hormonal control of their sexual behaviour?
is this a 100% thing?
only female mammals who are motivated to copulate during periods of non-fertility
what are the three findings that support the view that human primates are still effected by hormonal patterns>?
- more likely to engage in masturbation/ sex
- prefer male faces
- ovariectomy reduces sexual desire and frequency of sexual fantasies
What are the four relevant findings that question which ovarian hormone is responsible for female sexual desire?
- Roney and Simons - only high estradiol levels are related to human females sexual desire
- nonhuman female primates - replacement injections of T but not estradiol increased perceptivity of ovariwctomized, adrenalectomized female rhesus monkeys
- postmenopausal human females - estrogen therapy renews sexual interest sometimes, T therapy too sometimes
- T increases sex desire I post menopausal human females only in supraphysiological levels
what are anabolic steroids
steroids such as T that have anabolic (growth promoting) effects
is testosteron a useful anabolic?
nope, broken down soon after injection and has undesirable side effects
have chemists been able to synthesize anabolics that take along time to be broken down and are without side effects?
nope, only the former is available
what is the global lifetime prevalence rates for anabolic steroid use?
6.4% in males, 1.6% in females
why do we not fully understand the risks of testosterone abuse?
Bc its illegal, there are more than 100 derivatives, and users vary greatly in doses and admin patterns, hazardous effects are well documented in only a small proportion of users
wha are the main negative side effects of anabolic steroids on the internal organs?
cardiovascular effects can lead to death
oral anabolics can effect the liver and cause tumours
what are some of the less dangerous but unfortunate side effects of anabolic steroid use?
muscle spasms and pains, blood in the urine, acne, general swelling from the retention of water, tongue bleeding, nausea, vomiting, fits of depression and anger
Do large doses of anabolics increase sexual function in males (3)
No, can reduce gonadotropin release which
- reduces testicular activity causing testicular atrophy
- sterility
- Gynecomastia - breast growth in males
why do we think anabolic users get gynecomastia
presumably bc of the aromatization of anabolics to estrogens
what are the negative effects of anabolic abuse in females? (8)
- amenorrhea (cessation of menstruation)
- sterility
- hirsutism (growth of body hair)
- clitoral growth
- development of male body shape
- baldness
- breast shrinking
- deepening or coarsening of the voice
- not always reversible
what are the two mai points of concern about the adverse health consequences of anabolics
- use of anabolic during puberty is super risky
2. many adverse effects can take years to develop
