August 20, 2007

To add Spice: Don't "Bend it like Beckham"

viagra photosIn my previous article, On her majesty's service..., I wrote about how the sperms 'sniffed' and chased their way to the ovum till it nailed her down. But for the sperms to reach it's destination, it has to be deposited in the right place. Thats where this organ comes into functioning. Its name is penis. It is a very interesting organ. Just like the states of matter (solid, liquid, gas and plasma), it can be soft, rubbery, and small or it can be hard and long. It not only injects (ejaculates) sperms, but also it acts as a conduit for urine to flow out of our system. Hence it has been christened as the genitourinary organ.

When mosquitoes bite us, their proboscis get hard, for a soft one can not penetrate our skin. Likewise, it needs a hard (erect) penis to enter the vulva. You would say, its nothing great; the muscles there would do this job. Here, we have no skeletal muscles, only smooth muscles are there. When we are stimulated erotically, say by seeing an erogenic picture/video or in our vivid REM sleep dreams, the brain sends the corresponding electrical impulses through the nerves (nervi erigentes). These nerves secrete (neurotransmitter), neither nor-adrenaline, nor acetyl choline and hence are classified into a separate group called the NANC fibers. They secrete a chemical substance called nitric oxide (NO). (Nitrogen has five valence states and thus forms 5 different compounds with oxygen; nitrous oxide, N2O, is another compound that is used in medicine, as an anesthetic). This gas, previously called EDRF or the endothelium-derived relaxing factor, relaxes non-vascular smooth muscles in the corpora cavernosa of the penis, so that more blood can rush through it. The penis gets tough, as a result. Nitrous oxide stimulates/activates an enzyme called guanylyl cyclase to form cyclic GMP (guanosine mono phosphate). It is cGMP which brings about erection. Well, this (cGMP) is finally broken down by an enzyme, called phosphodiesterase and the erection ends. Sildenafil (the popular drug viagra), tadalafil etc inhibit phosphodiesterase, making the staff stay erected longer. It can act only if the nerve supply is intact. It also causes visual disturbances (impaired blue-green discrimination) as phosphodiesterase also plays a role in vision. Viagra can add vigor to the diabetics suffering erectile dysfunction. Bear in mind, erection for too long a duration can be hazardous, a condition known as priaprism. The penis may slough out! Viagra, can also be used to treat spasmodic arterial diseases such as Raynauds phenomenon (blanching, bluish and cold fingers;- in a nutshell), refractory pulmonary hypertension (raised blood pressure within the lungs resulting from vasospasm) and other diseases. However, since it dilates arterioles, there is a chance of hypotension, due to diminution in the resistance in the vascular bed, especially in persons taking concomitant drugs, such as nitroglycerin (used for the treatment of cardiac pain or angina) and antihypertensives (blood pressure lowering drugs). A few cases of myocardial infarction or heart attack have been reported. Prostaglandins such as alprostadil; phentolamine and apomorphine can help us add spice to our lives.

I would do injustice, if I did not mention how the testicles are kept in an air-conditioned chamber called scrotum, in this context. There is a heat radiator system that operate in the scrotum which keeps the temperature 2 degree Celsius (centigrade) lower than the core body temperature. It is effected by the position of the testicles (which is not in direct contact/apposed with the body) and the radiator fins just mentioned (the pampiniform venous plexus). This is necessary for effective spermatogenesis to occur. Persons who wear tight pants, works in hot environment (furnace workers, vehicle drivers exposed to engine heat) have impaired spermatogenesis and the chance of infertility (NOT impotence) is great in them.

Lastly, about the nomenclature of this post. 'Bend it like Beckham' is a movie about the legendary football player David Beckham and Victoria (of Spice Girls fame) is her wife. How Beckham makes the ball bend in 'mid air' can be explained by Magnus effect, which I have discussed in my previous post. I hope I have explained my stand.

No comments: