Small ruminants are often presumed to be at a higher risk of developing obstructive urolithiasis after early castration. However, the underlying pathophysiology and histological correlation of this assumption is unknown. This study examines the neuropeptide distribution of the lower urinary tract in male lambs in respect to castration status or a recent history of obstructive urolithiasis.

Various tissue samples were taken and examined. The sample consisted of 34 male lambs, aged six months (n = 11 early and n = 11 late castration; n = 12 intact), and 8 rams that had undergone necropsy due to fatal outcome after obstructive urolithiasis. Immunohistochemical stainings for substance P (SP), vasoactive intestinal polypeptide (VIP) and neurofilaments (NF) were performed and compared between the groups.

A significant reduction in immunoreactive signals of SP, VIP and NF was evident in the urolithiasis group (SP and NF: P < 0.0001; VIP: P = 0.02).

The results of immunohistochemistry suggest that castration had no effect on the content of neuropeptides, as well as the innervation density of the urethra in the male lambs. In the case of.

obstructive urolithiasis, the pattern of neuropeptide distribution was severely disturbed and cell damage lead to a reduction in detectable periurethral bundles of nerve fibers. The severe tissue damage was assumed to have a negative impact on the outcome of treatment, leading to complications such as urethral strictures. These, in turn, often result in relapses.

小反刍动物通常被认为在早期去势后发生阻塞性尿石症的风险较高。然而，这一假设的潜在病理生理学和组织学相关性尚不清楚。这项研究从去势状态或阻塞性尿石症的近期病史来看雄性羔羊下尿路的神经肽分布。

采集并检查各种组织样品。样本包括34个 公羊，年龄为6个月（n  = 11早期 去势，n = 11晚期去势；n = 12完整），以及8头因阻塞性尿路结石后的致命结果而进行了尸检的公羊。在两组之间进行了针对物质P（SP），血管活性肠多肽（VIP）和神经丝（NF）的免疫组织化学染色。

在尿石症组中SP，VIP和NF的免疫反应信号显着降低（SP和NF：P  <0.0001； VIP：P  = 0.02）。

免疫组化的结果表明去势对雄性羔羊神经肽含量以及尿道的神经支配密度没有影响。如果是。

在阻塞性尿路结石症中，神经肽的分布模式受到严重干扰，细胞损伤导致可检测的尿道周围神经纤维束减少。假定严重的组织损伤会对治疗结果产生负面影响，从而导致并发症，如尿道狭窄。这些反过来常常导致复发。