| Hormone | Source | Function | |
| 1. | Melanin | Pineal gland | Regulates body clock |
| 2. | LH | Posterior pituitary | Growth and maintenance of corpus luteum |
| 3. | Erythropoietin | \(\alpha-\)cells of Langerhans | Promotes formation of RBCs |
| 4. | Somatostatin | Hypothalamus | Inhibits release of GH |