False about funny current channel in hea: (A) It is a Na-K ATPase pump, (B) They are responsible for diastolic depolarization, (C) It is responsible for spontaneous rhythm producing tissue of hea, (D) They are voltage dependent channel only
Answer is A. Funny / leaky Na+ channels: - Hyperpolarization activated cyclin nucleotide gated (HCN) channels. More the hyperpolarization more the activation Equally permeable for Na+ & K+ After repolarization occur by K+ exit in pacemaker cells, next depolarization spontaneously reaches threshold, major pa in this spontaneous depolarization is by Na+ funny channel.