Upregulation of TRPC1/6 may be involved in arterial remodeling in rat.

BACKGROUND: Hypertension and its complications are associated with arterial remodeling. Transient receptor potential cationic channels (TRPCs) are important nonselective cationic channels that regulate calcium homeostasis in mammalian cell membranes. We aimed to study the expression of various TRPC isoforms in spontaneously hypertensive rat (SHR) carotid arterial remodeling and explore the relationship between SHR carotid arterial remodeling and TRPC expression. MATERIALS AND METHODS: Thirty male SHRs were randomly divided into three groups and sacrificed at ages 4, 8, and 18 wk, respectively, with matching control male Wistar-Kyoto rats (n = 10). Caudal artery systolic blood pressure (SBP) was measured every 2 wk. Carotid artery remodeling parameters including carotid artery wall thickness (MT), lumen diameter (LD), medial area, collagen area rate, and average nuclear area in media cells were determined after histologic staining. Real-time polymerase chain reaction and immunoblot assays were performed to assess TRPC expression. Carotid artery remodeling and TRPC expression were reevaluated after ginsenoside Rb1 treatment from eighth to eighteenth week. RESULTS: Carotid artery remodeling of SHRs was aggravated gradually with age and SBP, as well as MT, LD, MT/LD, medial area, average nuclear area in media cells, and collagen deposition, most obvious at 18 wk. Interestingly, expression of TRPC1, 3, and 6 increased with age and SBP, with TRPC1/6 showing significant differences between the Wistar-Kyoto and 18 wk groups; TRPC4/5 expression was unchanged and TRPC7 was barely detected. Importantly, after ginsenoside Rb1 treatment, TRPC1/6 expressions were significantly inhibited, SBP decreased, and the carotid artery remodeling in SHRs relieved. CONCLUSIONS: Upregulation of TRPC1 and TRPC6 may be involved in carotid arterial remodeling in SHRs.

1,4-Benzoxazine-3(4H)-ones as potent inhibitors of platelet aggregation: design, synthesis and structure-activity relations.

A series of novel potentially platelet aggregation-inhibiting 1,4-benzoxazine-3(4H)-one derivatives was designed and synthesized through Smiles rearrangement, reduction and acetylation reactions. The antiaggregatory activities of the target molecules on arterial blood samples from rabbits, expressed by IC50 values (µM), were then evaluated in vitro against ADP induced platelet aggregation. The favorable IC50 values of compound 8c (IC50=8.99 µM) and 8d (IC50=8.94 µM) indicated that these two compounds were the most potent molecules among all the synthesized compounds. A detailed molecular docking study to explore the interaction of compounds 8c and 8d with GP IIb/IIIa receptor showed that they these two compounds were docked into the active site of GPIIb/IIIa receptor. These results suggest that the 1,4-benzoxazine-3(4H)-one derivatives are promising lead compounds to develop new platelet aggregation inhibitors.