in heart rate, respiratory rate, and blood pressure. Vaginal lubrication has two types, psychogenic or reflexive, which are controlled by the regions of the spinal cord from T10 to L2 and S2 to S5, respectively. Orgasm has been directly investigated in laboratory-based studies with women with spinal cord injuries. Overall, only 52 percent of women with spinal cord injuries were able to stimulate themselves to orgasm, regardless of the nature of their injury (Sipski, 2001). Women with injuries of the sacral cord were significantly less likely to reach orgasm than women with spinal cord injuries at other, higher levels. Researchers therefore postulate that an intact sacral reflex is necessary for orgasm (Sipski, 2001; Benevento and Sipski, 2002).
Although much progress has been made, especially in the past 25 years, in understanding the basic biology of the nervous system and the complex pathways in the pathophysiology of spinal cord injuries that involve the immune, vascular, and nervous systems, much remains to be learned. As emphasized in the following chapters, this basic research is the underpinning of progress that will be made in developing therapeutic interventions.
Many research avenues remain to be examined to understand the biochemical mechanisms responsible for spinal cord injuries and thus the targets for the development of therapeutic interventions. Research is needed on the processes involved in cellular death and the immediate sequelae of apoptotic and necrotic cell death. The molecular mechanisms that promote and inhibit axonal regeneration need to be further explored, as do the molecular mechanisms that direct axons to their appropriate targets and regulate the formation and maintenance of appropriate and functional synaptic connections and circuitry.
Moving this research forward involves opportunities and challenges that are not isolated to spinal cord injury research. Rather, this research has far-reaching potential to both inform and be informed by many other fields of research and the efforts that are under way to examine other neurological diseases and conditions.
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Alexander CJ, Sipski ML, Findley TW. 1993. Sexual activities, desire, and satisfaction in males pre- and post-spinal cord injury. Archives of Sexual Behavior 22(3): 217-228.
Anderson AJ. 2002. Mechanisms and pathways of inflammatory responses in CNS trauma: Spinal cord injury. Journal of Spinal Cord Medicine 25(2): 70-79.