The voltage‐dependent K⁺ channel (Kv1.5) cloned from rabbit heart and facilitation of inactivation of the delayed rectifier current by the rat β subunit

Abstract

We have isolated a cDNA coding for a delayed rectifier K ÷ channel (RBKV1.5) from rabbit heart. The amino acid sequence of RBKV1.5 displays a homology to that of other K ÷ channels of Kvl.5 class. Overall amino acid identity between RBKV1.5 channel and Kvl.5 channel of other species is about 85%. RNA blot analysis revealed the expression of the primary transcript in various rabbit tissues, at the highest level in both the atrium and ventricle. When expressed in Xenopus oocytes, RBKV1.5 current showed a delayed rectifier type characteristics, which was converted to rapidly inactivating currents upon coexpression with a/3 snbunit.

Functional effects of the late sodium current inhibition by AZD7009 and lidocaine in rabbit isolated atrial and ventricular tissue and Purkinje fibre

“…While the Kv1.5 protein has been found in dog atria and ventricle, the electrophysiological correlate to Kv1.5 in the ventricle remaines to be clarified (Fedida et al, 2003). The presence and location of IK ur in rabbits are less clear, Kv1.5 mRNA has been found in both atria and ventricle (Sasaki et al, 1995) but the presence of the Kv1.5 protein or IK ur has not been studied in the rabbit. In goats, Kv1.5 mRNA is found in the atria (van der Velden et al, 2000).…”

Identification, cloning and expression of rabbit vascular smooth muscle Kv1.5 and comparison with native delayed rectifier K+ current

“…Cloning of RPVKv1.5 cDNA encoding RPVKv1.5 was cloned from mRNA derived from endothelium-denuded portal veins by standard RT-PCR using oligonucleotide primers based on the sequence of rabbit cardiac Kv1.5 (Sasaki et al 1995). Nucleotide sequence analysis of RPVKv1.5 revealed one long open reading frame encoding a protein of 598 amino acid residues which bears the hallmark features of the Kv superfamily of K¤ channels (Fig.…”

“…Reaction temperature was varied using a thermal cycler (Perkin-Elmer, Norwalk, CT, USA) as follows: 98°C for 30 s, 60°C for 30 s and 72°C for 2 min, for 35 cycles. The sense primer corresponded to nucleotides −9 to +11 of rabbit cardiac Kv1.5 (Sasaki et al 1995) and the antisense primer to nucleotides 1804 to 1823. The 5'-ends of the sense and antisense primers contained an EcoRI and a BamHI site, respectively, to facilitate subcloning.…”

Characterization of a Slowly Inactivating Outward Current in Adult Mouse Ventricular Myocytes

“…Kv1.5 channel has been cloned from mammalian hearts of various species including rat, 18 rabbit, 19 human, 20,21 and mouse. 22 By using a dominant negative approach we demonstrated 11 that overexpression of Kv1.1N206, a truncated Kv1.1 cDNA, in the mouse heart resulted in a prolongation of APD and LQT.…”