ACE also known as CD105, ACE1 is a crucial carboxy-terminal dipeptidyl exo-peptidase involved in the renin-angiotensin system, where ACE converts Angiotensin I into the potent vasopressor hormone Angiotensin II, thereby regulating blood pressure and electrolyte balance. ACE also plays a vital role in inactivating bradykinin, a vasodepressor peptide, which is essential for maintaining fluid and electrolyte homeostasis. Structurally, ACE interacts with several proteins, including renin, which initiates the conversion of angiotensinogen to Angiotensin I, and the Angiotensin II receptors (AT1 and AT2), which mediate the physiological effects of Angiotensin II. Additionally, ACE interacts with integrins and the sodium/hydrogen exchanger 3 (NHE3), influencing cellular signaling and ion transport processes. There are two primary isoforms of ACE: pulmonary ACE (ACEP), a glycoprotein expressed in vascular endothelial cells of the lung, liver, adrenal cortex, pancreas, kidney, and spleen, and testicular ACE (ACET), which is exclusively expressed in adult testis by developing sperm cells, specifically late pachytene spermatocytes.