It remains unclear how pituitary pars intermedia dysfunction (PPID) and pergolide treatment (Prascend [pergolide tablets]) affect endocrine and immune function in horses. To evaluate these effects, blood was collected regularly from 28 university-owned horses (10 Non-PPID, 9 PPID control [PC], and 9 PPID treatment [PT]) over approximately 15 mo. Pergolide treatment was initiated after Day 0 collections. Analyses included ACTH, insulin, total cortisol, free cortisol, complete blood counts, plasma myeloperoxidase, and cytokine/receptor gene expression in basal whole blood and in vitro stimulations (PMA/ionomycin, heat-inactivated Rhodococcus equi, and heat-inactivated Escherichia coli) of whole blood and peripheral blood mononuclear cells (PBMCs). The results were analyzed using a linear mixed model (SAS 9.4) with significance set at P < 0.05. Significant group (P = 0.0014) and group-by-time (P = 0.0004) effects were observed in resting ACTH such that PT horses differed from Non-PPID horses only at Day 0. PT horses had significantly lower changes in ACTH responses to thyrotropin-releasing hormone stimulation tests than PC horses at non-fall time points only, mid-late February 2018 (P = 0.016) and early April 2018 (P = 0.0172). When PT and PC horses did not differ, they were combined before comparison to Non-PPID horses. No significant group or group-by-time effects were seen in resting insulin, total cortisol, or free cortisol; however, significant time effects were observed in these measures. PPID horses had lower absolute lymphocyte (P = 0.028) and red blood cell (P = 0.0203) counts than Non-PPID horses. In unstimulated whole blood, PPID horses had increased IL-8 expression compared with Non-PPID horses (P = 0.0102). In addition, PPID horses had decreased interferon γ production from PBMCs after stimulation with R. equi (P = 0.0063) and E. coli (P = 0.0057) and showed increased transforming growth factor β expression after E. coli stimulation (P = 0.0399). The main limitations of this study were a limited sample size and an inability to truly randomize the PPID horses into treatment groups. Resting ACTH is likely the best choice for determining successful responses to pergolide. Neither PPID nor pergolide appears to influence insulin, total cortisol, and free cortisol. As measured, systemic immune function was altered in PPID horses, and it is likely that these horses are indeed at increased risk of opportunistic infection. Despite reducing ACTH, pergolide treatment did not appear to influence immune function.

目前尚不清楚垂体中间部功能障碍（PPID）和培高利特治疗（Prascend [培高利特片]）如何影响马的内分泌和免疫功能。为了评估这些效果，我们在大约 15 个月内定期从 28 匹大学拥有的马（10 匹非 PPID、9 匹 PPID 控制 [PC] 和 9 匹 PPID 治疗 [PT]）收集血液。在第 0 天收集后开始培高利特处理。分析包括ACTH、胰岛素、总皮质醇、游离皮质醇、全血细胞计数、血浆髓过氧化物酶和基础全血和体外刺激（PMA/离子霉素、热灭活的马红球菌和热灭活的大肠杆菌）中的细胞因子/受体基因表达) 全血和外周血单核细胞 (PBMC)。使用线性混合模型 (SAS 9.4) 分析结果，显着性设置为P < 0.05。在静息 ACTH 中观察到显着的组 ( P = 0.0014) 和逐组 ( P = 0.0004) 效应，因此 PT 马仅在第 0 天与非 PPID 马不同。 PT 马对促甲状腺素的 ACTH 反应变化显着较低-仅在非摔倒时间点、2018 年 2 月中下旬（P = 0.016）和 2018 年 4 月上旬（P= 0.0172）。当 PT 和 PC 马没有区别时，在与非 PPID 马比较之前将它们合并。在静息胰岛素、总皮质醇或游离皮质醇中未观察到显着的组或组间效应；然而，在这些措施中观察到了显着的时间效应。PPID 马的绝对淋巴细胞 ( P = 0.028) 和红细胞 ( P = 0.0203) 计数低于非 PPID 马。在未受刺激的全血中，与非 PPID 马相比，PPID 马的 IL-8 表达增加（P = 0.0102）。此外，PPID 马在用R刺激后减少了 PBMC 产生的干扰素 γ 。equi ( P = 0.0063) 和E 。大肠杆菌（P= 0.0057) 并显示E后转化生长因子 β 表达增加。大肠杆菌刺激（P = 0.0399）。这项研究的主要局限性是样本量有限，并且无法真正将 PPID 马随机分配到治疗组中。静息 ACTH 可能是确定对培高利特的成功反应的最佳选择。PPID 和培高利特似乎都不影响胰岛素、总皮质醇和游离皮质醇。根据测量，PPID 马的全身免疫功能发生了改变，这些马可能确实处于增加的机会性感染风险中。尽管降低了ACTH，培高利特治疗似乎并未影响免疫功能。