|MadSci Network: General Biology|
Glen: There is a direct relationship to testicular size and fertility in heathy mammals. However, there are certain circumstances where testes size may not be related to fertility. For example, in the case of testosterone (T) deficiency, the testes may actually be larger than normal. This is due to the loss of T feedback inhibition of Luteinizing hormone (LH) from the anterior lobe of the pituitary gland. As LH causes the testes to enlarge, if the secretion of LH is not kept in check by T feedback inhibition, the testes could be stimulated to increase in size. As T is necessary for spermatogenesis, the T deficiency would lead to infertility, but the testes size would remain large because of LH stimulation. Of course, other conditions such as testicular cancers will change the size of the glands and can wreak havoc on fertility. David Mallory Department of Biological Sciences Marshall University Huntington, WV
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