BS22. Study of autonomic nervous system activity based on gender differences

Introduction The autonomic nervous system is an extensive neural network whose main role is to regulate the milieu interieur by controlling homeostasis and visceral functions. Differences in the autonomic system activity may be due to differences in afferent receptor stimulation, in central reflex transmission, in the efferent nervous system and in post synaptic signaling. Gender differences in the autonomic nervous system may be present because of developmental differences or due to the effect of prevailing levels of male or female sex hormones. Although researchers from myriad of disciplines are beginning to appreciate the importance of considering gender differences in the design and interpretation of their studies, this is an area that is full of potential pitfalls. A female’s reproductive status and ovarian cycle have to be taken into account when studying gender differences in health and disease states. Methods The present study was conducted on 200 medical students in the age group of 17–25 years. They were allocated into two groups: Group 1 comprised of young healthy males (n = 100). Group II comprised of young healthy female (n = 100) and this group underwent two phases of examination: First examination was done during late follicular phase between 10th and 13th day (Group IIA) and the second examination was done during mid luteal phase between 17th and 22nd day (Group IIB) of ovarian (menstrual) cycle. Autonomic function testing to assess sympathetic and parasympathetic activity was done. Results The finding of the present study indicated that there is marked difference in autonomic functions in males and females and these differences vary with the phase of menstrual cycle of females. This study revealed that there is predominant sympathetic activity in males compared to females whereas there is significant parasympathetic activity in females during late follicular phase compared to males. However, parasympathetic activity was reduced while sympathetic activity was increased in females during mid luteal phase. Conclusion It has been observed with the obtained results that significant gender related differences exist in the autonomic nervous system activity. As these differences vary with the phase of menstrual cycle in females, it is important to compare males with two or more groups of females where the stage of the menstrual (ovarian) cycle is known.