
Interstitial cystitis (IC) is a chronic, debilitating pelvic pain syndrome, characterized by recurrent urinary frequency, urgency, and pain referable to the lower urinary tract. These symptoms often appear acutely, and follow a waxing and waning course. The etiology of this disease is unknown, and no acceptable long-term therapy exists. A spontaneously occurring disease analogous to IC occurs in domestic cats referred to as feline interstitial cystitis (FIC). This model of IC may be the most suitable model to investigate the disease because it is a naturally occurring disease, and clinical signs are exacerbated by stress, which occurs in the human counterpart. To further investigate the stress response systems in the cat with FIC, we evaluated catecholamines and their metabolites as well as the hypothalamic-pituitary-adrenal axis in cats with FIC by evaluating urine cortisol/creatinine ratios and response of the adrenal gland to exogenous ACTH. When healthy cats were stressed, cortisol and catecholamines increased, but returned to baseline within hours to days. In our study, cats with FIC did not appear to have this capability. Their catecholamines remained elevated, while their adrenal cortex response was blunted. An apparent “dissociation” of the two major stress response systems was found. The overarching premise of our studies is that FIC is not just a bladder disorder but involves complex interactions of the nervous, endocrine, and cardiovascular systems. How these systems communicate and manifest as FIC in some cats, but not in others remains to be determined. However, understanding that these interactions occur, is important for clinicians to help better evaluate and treat both humans and cats with IC.
More...