Dimorphism, sexual

Steroid Hormones and Neurosteroids. Steroids (qv) can affect neuroendocrine function, stress responses, and behavioral sexual dimorphism (78,79) (see Steroids). Mineralocorticoid, glucocorticoid, androgen, estrogen, and progesterone receptors are localized in the brain and spinal cord. In addition to genomic actions, the neurosteroid can act more acutely to modulate the actions of other receptors or ion channels (80). Pregnenolone [145-13-17, ( ) dehydroepiandosterone [53-43-0] C H2 02 (319) are excitatory neurosteroids found in rat brain, independent of adrenal... 

The mammalian and avian immune systems function similarly both incorporate humoral and cell-mediated cytotoxic mechanisms, " and are thought to share a 160m year old relationship with the reptilian immune system. The immune system of mammals shows sexual dimorphism " a greater immune response is normally observed in females, which has been attributed to differences in steroid hormone concentration. In the toad Bufo regularis, sexual dimorphism of the immune system is also apparent. ... 

Long bone metrics and sexual dimorphism in a 19th-century historical sample. Paper... 

Milnes, M.R., Bryan, T.A., and Katsu, Y. et al. (2008). Increased post hatching mortality and loss of sexually dimorphic gene expression in alligators Alligator mississippiensis) from a contaminated environment. Biology of Reproduction 1 07.064915. 

Phytoestrogens have also been shown to have behavioural effects in rodents including increases in sexual activity (Patisaul et al, 2001) and a reversal of sex-specific behaviours (Lund et al, 2001 Flynn et al, 2000). In rodents, the sexually dimorphic nucleus of the preoptic area (SDN-POA) is located in the hypothalamic region of the brain. This area of the brain controls... 

FABER K A, HUGHES c L JR. (1993) Dose-responsive characteristics of neonatal exposure to genistein on pituitary responsiveness to gonadotrophin releasing hormone and volume of the sexually dimorphic nucleus of the preoptic area (SDN-POA) in postpubertal castrated female rats. Reprod Toxicol. 1 35-9. 

FLYNN K M, FERGUSON s A, DELCLOS K B and NEWBOLD R R (2000a) Effects of genistein exposure on sexually dimorphic behaviors in rats. Toxicol Sci. 55 (2) 311-19. 

Fig. 5.9(a) Sexually dimorphic processing in Ferret differential activation of central nuclei by heterosexual cues. Fos-induction levels moderate/high, L — female, and R — male, brains (from Wesinger and Baum, 1997). 

Fig. 5.10 Sexually Dimorphic Network Structural and/or functional distinctions at peripheral to central levels (I to III) in the rat AOS (from Segovia and Guillamon, 1993).

Chen W.P., Witkin J.W. and Silverman A.J. (1990). Sexual dimorphism in the synaptic input to gonadotropin-releasing hormone neurons. Endocrinology 126, 695-702. 

Cherry J. and Lepri J.J. (1986). Sexual dimorphism and gonadal control of ultrasonic vocalizations in adult pine voles Microtus pinetorum. Horn Behav 20, 34-48. 

Dorries K.M., Adkins-Regan E. and Halpem B.P. (1995). Olfactory sensitivity to the pheromone, androstenone, is sexually dimorphic in the pig. Physiol Behav 57, 255-259. 

Herrada G. and Dulac C. (1997). A novel family of putative pheromone receptors in mammals with a topographically oiganised and sexually dimorphic distribution. Cell 90, 763-773. 

Larriva-Sahd J.A., Matsumoto A. and Sumoto A. (1994). The vomeronasal system and its connections with sexually dimorphic neural structures. Zool Sci 11, 495-506. 

Saltiere-Imerly R.B., Young B.J. and Capozza M.A. (1989). Estrogen differentially regulates neuropeptide gene expression in a sexually dimorphic olfactory pathway. Proc Natl Acad Sci 86, 4766-4770. 

Simerly R. (1990). Hormonal control of neuropeptide gene expression in sexually dimorphic olfactory pathways. Trends Neurosci 13, 104-110. 

Ulibarri C. and Yahr R (1996). Effects of androgens and estrogens on sexual differentiation of sex behavior, scent marking and the sexually dimorphic area of the gerbil hypothalamus. Horn Behav 30, 107-130. 

Valencia A., Collado P., Cales J.M., et al. (1992). Postnatal administration of dihydrotestosterone to the male rat abolishes sexual dimorphism in the accessory olfactory bulb a volumetric study. Dev Brain Res 68, 132-135. 

Wesinger S.R. and Baum M. (1997). Sexually dimorphic processing of somato- and chemosensory inputs to forebrain LHRH neurons in mated ferrets. Endocrinology 138, 1121-1129. 

Gogos, J. A., Morgan, M.,Luine, V. etal. Catechol-O-methyl-transferase-deficient mice exhibit sexually dimorphic changes in catecholamine levels and behavior. Proc. Natl Acad. Sci. U.S.A. 95 9991-9996,1998. 

Meyer, J.M. (2006) Sexually dimorphic social development and female intrasexual chemical signaling of African elephants (Loxodonta africana). M.Sc. thesis, Georgia Southern University. 

Little, A. C., Burt, D. M., Penton-Voak, I. and Perrett, D. I. (2001) Self-perceived attractiveness influences human female preferences for sexual dimorphism and symmetry in male faces. P. Roy. Soc. Lond. B Bio. 268, 39 14. 

Frank, L.G., Glickman, S.E. and Powch, I. (1990) Sexual dimorphism in the spotted hyaena (Crocuta crocuta). J. Zool. Lond. 221, 308-313. 

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