Quiz 44: Animal Behavior
Sildenfail also known as Viagra is a vasoactive agent, which is used to treat erectile dysfunction in males; and it is also decrease the symptom levels in patients who have pulmonary arterial hypertension syndrome. Sildenfail is a phosphodisesterase-5 inhibitor. Phosphodiesterase is an enzyme present in the corpus cavernosum, an erectile tissue in penis of males particularly in high concentrations. Sildenfail increases cGMP, a second messenger levels by inhibiting its breakdown through phosphodiesterase. Thus, increased cGMP levels will increase the blood flow in penis, which facilitates the generation and maintenance of an erection in males.
Many drugs like legal and illegal drugs may have numerous side effects, which affects the sexual behaviour of users. Some research works of neurophysiology and neuropharmacology provides evidence that continues work of drugs on the nervous system may cause the mental illness by imbalances in neurotransmitters. Many drugs denature the protein structures that damage several tissues and vital organs like liver and brain. Some drugs like alcohol, nicotine, and MDMA (3,4-methylenedioxy-methamphetamine) may increase the sensual and erotic sensations. They may cause the temporary erectile dysfunction which inhibits the sexual intercourse itself.
Male reproductive system includes a pair of testis, accessory ducts, glands and the external genitalia. Each testis contains testicular lobules, which have seminiferous tubules. In between the seminiferous tubules there are connective tissue present in small groups which are called interstitial or Leydig's cells which secrets androgens i.e., testosterone. Sometimes, these leydig's cell may form tumours in testicles. The causes of leydig's cell tumour not known. They may be caused by mutations in genes, which encodes testosterone hormone. These tumours are common in early stage of puberty in young boys. There are no symptoms of leydig's tumours. If symptoms occur, they may include: • pain in lower abdomen or back side • heaviness in scrotum • Enlargement, swelling and discomfort may present in either testicles If tumours spread in entire body they may cause pains of other body organs like lungs, liver, brain, abdomen regions and pelvic regions.