(1) Hypothalamus :

It secretes following hormones:

(a) Hypothalamus: Hormones secreted by the hypothalamus include:

(1) Releasing hormones: These hormones stimulate the secretions of the pituitary hormone. Examples of these hormones are:
(i) Gonadotrophin-releasing hormone
(ii) Thyrotrophin-releasing hormone
(iii) Somatotropin-releasing hormone
(iv) Adrenocorticotrophin-releasing hormone

(2) Inhibiting hormones: These hormones inhibit the secretions of the pituitary hormone. Examples of these hormones are:
(i) Somatostatin
(ii) Growth-inhibiting hormone
(iii) Melanocyte-inhibiting hormone

(2) Pituitary gland :
 Pituitary gland is divided into.

(i) Adeno hypophysis (ii) Neuro hypophysis 

Hormones secreted by the adenohypophysis are:
(i) Growth hormone (GH)
(ii) Prolactin
(iii) Thyroid-stimulating hormone (TSH)
(iv) Adrenocorticotrophic hormone (ACTH)
(v) Luteinizing hormone (LH)
(vi) Follicle-stimulating hormone (FSH)
(vii) Melanocyte-stimulating hormone (MSH)

Hormones secreted by the neurohypophysis are:
(i) Oxytocin
(ii) Vasopressin

(3) Thyroid gland :

Follicle cells of thyroid gland secrete two hormones.

Tetraidothyronine (T₄)

Tridothysonine (T₃)

C cells of thyroid also secrete thyrocalcitonin.

(4) Parathyroid gland : It secretes parathyroid hormone .

(5) Adrenal gland :
The adrenal gland has outer
(i) Adrenal cortex
(ii) Adrenal medulla.

(i) Adrenal cortex has three parts :

(a) Outer part or zona glomerulosa : It secretes mineral corticoids.

(b) Middle part or zona fasciculata : It secretes glucocorticoids,.

(c) Inner part or zona reticularis : Both middle and inner part secrete sex corticoids.

(ii) Adrenal medulla :
It secretes
i. epinephrine or adrenaline hormone
ii. noradrenaline or norepinephrine hormone.

(6) Pancreas : Its cells called Islets of Langerhans are of two types :

(a) α cells : These secrete glucagon hormone. (b) β cells : These secrete insulin.

(7) Testis: It has interstitial cells or cells of leydig which secrete androgens mainly testosterone.

(8) Ovary: The graafian follicle secretes estrogen hormone.

Corpus luteum secretes progesterone and relaxin hormone.

(9) Thymus :
It secretes thymosin hormone.


(10) Atrium : The atrial wall secretes atrial natiuretic factor (ANF)

(11) Kidney : The juxtaglomerular cells of kidney produce erythropoietrin hormone.

(12) G–1 Tract :

It secretes following hormones.
(i) secretin
(ii) cholecystokinin (CCK)
(iii) enterogastrone or gastric inhibitory peptide (GIP)
(iv) Villikinin
(v) Duocrinin
(vi) Enterocrinin.