Biology of Reproduction Summers |
Endocrinology Homeostasis/Feedback Adult Female Steroid Production Ovulation |
Adult Male Gonadal Axis Regulation Sexual Differentiation Sexual Behavior Puberty |
Reproductive Cycling Estrous Cycles Menstrual Cycle Menopause Fertilization |
Fertilization Systems Gamete Interaction Pregnancy Labor and Parturition Lactation |
Sexual Response & Behavior Pheromones STDs text: Human Reproductive Biology4th Edition- RE Jones & KH Lopez,: pp 235 - 241 Acronyms/Abbreviations end |
XXVII. Pheromones A. exocrines which change physiology or behavior of another individual 1. regulated by hormones B. sexual attractants are pheromones 1. releasing pheromones trigger a rigid stereotyped response a. typical of insects 2. signaling pheromones elicit complex modifiable responses to chemical cues a. sensed primarily by accessory olfactory (vomeronasal) organs in vertebrates i. linked neurally with limbic and hypothalamic nuclei controlling reprodcution and sexual behavior (1) GnRH cells in adult hypothalamus originate as accessory olfactory neurons and migrate to the POA and ARC ii. human VNO is electrophysiologically stimulated by skin or axillary extracts (1) androstenes activate female VNO more (a) women are attracted to scents of men that are most unlike themselves in MHC genes major histocompatibility complex (2) estrenes activate male VNO more b. vaginal secretions of female hamsters contain aphrodisin i. attract males ii. stimulate sexual behavior (1) olfactory lesions completely block courtship and sexual behavior (2) vaginal secretions applied to the hindquarters of males makes that male sexually attractive to other males iii. learned (1) can be conditioned (a) androgens Ý attractiveness of vaginal secretions in both males and females b. androgens can be pheromones i. androgens secreted into salivary glands of male pigs (1) androgen becomes airborne by exhalation (a) induces lordosis in receptive females ii. T in male mouse urine elicits Ý aggression from other males c. estrogens can be pheromones i. E2 secreted onto the skin of female garter snakes attract many males and stimulate formation of mating ball d. prostaglandins can be pheromones i. the same PGF2a released during ovulation are released into the water and trigger sexual behavior in male goldfish d. pheromones in urine of estrus female rat: i. signals estrus to male e. copulins from female Rhesus monkeys i. Ý male sex drive f. humans i. copulins are in vaginal secretion near ovulation (1) vaginal secretions near ovulation are most attractive to men (2) vaginal secretions applied to women Ý their sexual attractiveness ii. axillary secretions Ý attractiveness C. priming pheromones induce physiologcial changes in the recipient (usually takes 48h) 1. D male reproductive physiology a. hamster vaginal secretions ® quick elevation of male T i. reduce aggression b. progestins can be pheromones i. goldfish female preovulatory follicles secrete progestins into the water (1) Ý gonadotropins ® Ý sperm production in males 2. D female reproductive physiology a. pheromones in urine of mature male mice: i. synchronize estrous cycles b. pheromones from female mice suppress ovarian function i. probably by ¯ LH and FSH c. pheromones from male prairie voles activate ovarian estrogen secretion i. estrus and ovulation do not occur in the absence of males 3. humans a. musk-like oders can be smelled by adult women; not by children or males i. only near ovulation b. axillary secretions synchronize menstrual cycles for cohabiting women c. frequency of exposure to men (axilla) can influence menstrual regularity D. gamones induce sexual development (also priming) 1. mature male mice urine also a. speeds puberty in females b. female urine delays puberty 2. nipple pheromone in rabbits a. enables young to locate and grasp nipple E. allomones and kairomones are interspecies attractants