Effects of acute and chronic midthoracic spinal cord injury on neural circuits for male sexual function. I. Ascending pathways

作     者：Hubscher, CH Johnson, RD 

作者机构：Univ Florida Coll Vet Med Dept Physiol Sci Gainesville FL 32610 USA Univ Florida Inst Brain Gainesville FL 32610 USA 

出 版 物：《JOURNAL OF NEUROPHYSIOLOGY》 (神经生理学杂志)

年 卷 期：1999年第82卷第3期

页      面：1381-1389页

核心收录：

学科分类：0710[理学-生物学] 1001[医学-基础医学(可授医学、理学学位)] 07[理学] 071003[理学-生理学] 

基　　金：NINDS NIH HHS [NS-35702] Funding Source: Medline 

主　　题：急性病 传入通路/病理生理学 慢性病 挫伤/病理生理学 电刺激 后肢/病理生理学 阴茎/病理生理学 物理刺激 大鼠 Wistar 性行为 动物/生理学 脊髓损伤/病理生理学 胸部 泌尿生殖系统/病理生理学 动物 男(雄)性 大鼠 

摘      要：Normal male reproductive function, particularly ejaculation, requires the integrity of urogenital sensory input and its ascending spinal projections. After midthoracic chronic spinal cord injury, sexual dysfunction occurs in both rats and humans. Neurons in the medullary reticular formation (MRF) are involved in the processing of bilaterally convergent sensory inputs from multiple cutaneous, mucocutaneous, and visceral regions of the body, including the penis and male urogenital tract. A variety of acute and chronic lesions were used to determine the midthoracic location of ascending spinal pathways conveying sensory input from the penis and male urogenital tract to MRF. A total of 371 single neurons were recorded in the MRF of 34 urethan-anesthetized mature male rats. Twenty-seven rats received a chronic T-8 dorsal (DHx) or lateral (LHx) hemisection or contusion (Cx) injury 30 days before the terminal electrophysiological experiments. In addition, nine dorsal nerve of the penis (DNP)responsive MRF neurons in seven intact control animals were tested completely both before and after various select acute spinal cord lesions. The chronic lesion data indicate that low and high threshold input from the penis (mucocutaneous) and male urogenital tract (visceral) ascend bilaterally within the dorsal quadrant at T-8 as opposed to high threshold input from the hindpaws (cutaneous), which ascends unilaterally in the ventrolateral quadrant (VLQ). The acute lesion data indicate that the low-threshold information conveyed from the penis and male urogenital tract ascends in the dorsal columns, as opposed to the high-threshold nociceptive inputs that ascend bilaterally in the dorsolateral quadrant (DLQ). These results, as well as previous data on ascending projections from female reproductive organs within the dorsal columns and DLQ to other caudal brain stem nuclei, provide evidence for ascending pathways conveying nociceptive information centrally via the DLQ. This spinal gray-DL