5 de diciembre de 2021

 

Biology of Sexuality: Participation of brain, hormones, vessels and neurotransmitters
Enrique Canchola Martínez
Departamento de Biología de la Reproducción
Universidad Autónoma Metropolitana-Iztapalapa
Ciudad de México, México
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01122021

Abstract.
This article briefly reviews the role of hormones, blood vessel health, neurotransmitters, and the nervous system in the modulation of sexuality.

Keywords: biology of sexuality, hormones and nervous system

1.-Introduction
Sexuality is one of the most important and pleasant functions of life, since reproduction depends on it and is a very important part of the mental and physical health of the individual, so that sexuality is fully realized a delicate concert of at least four conditions for it to be carried out fully and satisfactorily:
1. Adequate levels of hormones, 2. Healthy blood vessels, vascular integrity, specifically leaky of capillaries, 3 Adequate synthesis and release of neurotransmitters involved in the deployment and vascular integrity, healthy blood vessels, specifically leaky capillaries, and 4. Normal nervous system function

1.-Adequate levels of hormones
It has been known for a long time that the balance in the levels of hormones is essential to induce desire and erotic-sexual fantasies, to carry out their functions hormones act in the central and peripheral nervous system, specifically in the hypothalamus and the brain stem where the reproductive programs are integrated and throughout the body, particularly in the sexual organs so that they can interact. The most important hormones required to induce sexual behavior are androgens, estrogens, progestins, mineral and glucocorticoids, thyroid hormones, and pancreatic hormones. The desire and the possibility of sexual interaction depend on hormones, in men androgens and estrogens are important, while in women estrogens and progesterone are necessary (1,2)

2.-Vascular integrity
The integrity and normal function of the circulatory system, normal blood cell and plasma volume, blood pressure within physiological ranges, vascular elasticity and normal lipid levels are essential to engorge the sexual organs and induce sexual desire. It is known that vascular alterations are responsible for erectile dysfunction and decreased sexual interest, through the alteration of the synthesis of nitric oxide and other molecules in the endothelium of the vessels and the decrease in the perfusion of these molecules due to the thickening or stiffness of the capillary endothelium. The degree and time of erection of the penis, the clitoris and an area called the G-spot depend on genital engorgement. (3, 4)

3.-Normal levels of neurotransmitters
Neurotransmitters are substances that allow communication between the different neurons of the nervous system, are synthesized in the pre-synaptic neuron and are released by the electrical event. The main neurotransmitters that participate in sexual behavior are acetylcholine, dopamine, norepinephrine, GABA and serotonin, although there are other substances such as oxytocin and enkephalins that, although they are not nerve transmitters, have the ability to modulate sexual behavior. To have a comprehensive vision of the participation of neurotransmitters in sexuality, let us remember that the limbic system or circuit is fundamental, this nervous circuit begins in the hypothalamus where serotonin is produced, which induces the release of enkephalins that act in the ventral region. tegmental inhibiting the action of gamma amino butyric acid (GABA), an inhibitory neurotransmitter from the substantia nigra, which allows the secretion of dopamine and its stimulation to the acumbens, the hippocampus and the amygdala where pleasurable sexual behaviors are integrated, abnormalities of this circuit, whether at the nervous, chemical or receptor level for transmitters, alters sexuality
Although it is not yet entirely clear which neurotransmitters facilitate or inhibit male or female sexual behavior, the increase in dopamine and norepinephrine and the decrease in serotonin facilitate the deployment of female sexual behavior, while the increase in dopamine and acetylcholine and the decrease in GABA and serotonin facilitate male sexual behavior. 5, 6)

4.-Normal Nervous Function
Sexuality is the product of a reflex arc in which the different receptors of the
sensory organs, that is, through sight, hearing, taste, touch and the construction of an imagination, sexuality programs are activated, although it is important to mention again that adequate levels of hormones are indispensable as that these constitute the other indispensable part for the integration of the sexual function; in such a way that even if there is sexual stimulation if there are no hormonal levels, sexual behavior is not displayed or even if there are adequate levels of hormones, if there are no sexual stimuli, sexual behavior is not induced. The sexual reflex arc is made up of sexual receptors that translate the stimulus into an electrical nervous event, sensitive nerves, an integrating center, in the central nervous system, where the type and intensity of the response is decided, motor nerves and an effector that translates the nervous response in a biological activity. Alterations of this system lead to a sexual disease that can be of hormonal, nervous or psychological etiology or of a part of all of them. (7, 8)

Conclusion
From the above it is concluded that the delicate orchestration of sexual hormones, the nervous system with its hormones and neurotransmitters is required for a healthy intelligent sexuality full of passion, eroticism and love to exist.

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