All of the following statements are incorrect except
1. Secretin acts on endocrine part of pancreas and stimulates secretion of water and bicarbonate ions
2. Leydig cells present in seminiferous tubules and corpus luteum are major target of LH
3. Epinephrine, melanin and thyroxine are derivates of aminoacid tyrosine
4. cAMP acts as secondary messenger for aldosterone