Endocrinology, Blood, & Cardiac Physiology

Exocrine

No hormone released, release substances into lumen or outside of body & need blood transport

Hormone Stimulation

Release of another hormone triggers release of the hormone

Humoral Stimulation

Changes in level of nutrient or ion in the blood triggers release of the hormone

Nervous System Stimulation

Stimulation by the nervous system triggers release of the hormone

Local Hormones

No blood transport

Autocrine Stimulation

Hormone binds to the same cell (ex. cancer cells)

Paracrine Stimulation

Hormone binds to neighboring cell

Circulating Hormones

Need blood transport

Steroid hormone

Lipid-soluble & formed from cholesterol

Biogenic Amines

Water-soluble & derived from amino acid that is modified

Proteins

Water-soluble & consists of amino acid chains

Water-Soluble Hormones

Dissolved in blood & can not cross membrane

Lipid-Soluble Hormones

Need carrier proteins

Hormone Release

Stimulated by another hormone, certain chemicals, or nervous system

Synergistic Effect

The combined effect of hormones is greater than additive

Permissive Effect

Allows another hormone to have its full effect

Antagonistic Effect

Opposing effects of two hormones

Posterior Pituitary

Nervous tissue

Anterior Pituitary

Glandular tissue & stimulated by hormones from the hypothalamus to synthesize and release different hormones

Oxytocin

Synthesized in hypothalamus, stored & released, stimulates uterus contraction, & stimulates milk ejection

Antidiuretic Hormone (ADH)

Synthesized in hypothalamus, stored & released, & targets kidneys to increase water reabsorption back to blood stream

Portal Veins

Transport hormones from hypothalamus to anterior pituitary

Plexus

Capillaries in one organ

Two Plexus

Two organs connected by the portal vein

Thyroid-Stimulating Hormone (TSH)

Stimulates thyroid gland to release thyroid hormone

Prolactin (PRL)

Acts on mammary glands to influence gland growth and stimulate milk production

Follicle-Stimulating Hormone (FSH) & Luteinizing Hormone (LH)

Act on gonads (testes & ovaries) to stimulate development of gametes (sperm & oocyte), & release hormones

Adrenocorticotropic Hormone (ACTH)

Acts on the adrenal cortex to cause release of glucocorticoids (ex. cortisol)

Growth Hormone (GH)

Stimulates release of IGFs from the liver, which synergistically act on all body tissues, especially cartilage, bone, muscle, & adipose connective tissue to stimulate growth

Negative Feedback

The downstream hormone feeds back to suppress upstream hormone secretion

Short-Loop Negative Feedback

Hormone released from anterior pituitary inhibits hormone release from hypothalamus

Long-Loop Negative Feedback

Hormone released from peripheral glands inhibits hormone release from hypothalamus and pituitary gland

Thyroid Hormone

Increases metabolism rate & increases basal metabolic rate

Grave’s Disease- Hyperthyroidism

Thyroid-stimulating immunoglobulin (TSI) binds to TSH receptor on the thyroid gland causing the thyroid gland to enlarge

Hypothyroidism

Low levels of thyroid hormone (T3/T4) → high level of TRH & TSH → enlargement of thyroid gland → levels of T3/T4 remain low

Parathyroid Gland

Synthesizes parathyroid hormone

Release of Cortisol

Influenced by circadian rhythm & stress

Pancreas

Both an endocrine & exocrine organ

Function of Blood

Transportation, regulation, & protection

Composition of Blood

Plasma → buffy coat (white blood cells) → erythrocytes (red blood cells)

Albumin

Produced by liver, most abundant plasma protein, & contributes to colloid osmotic pressure

Globulin

Alpha/beta globulin transport water-insoluble molecules (lipids & vitamins)

Fibrinogen

Participate in blood clotting

Erythrocytes

Red blood cells & O2 transport

Leukocytes

White blood cells & immune system defense

Platelets

Cell fragments & stops bleeding/maintain vascular health

ABO Blood Group

Based on antigen A & B

Rh Blood Group

Based on antigen D

Type A Blood

Surface antigen A & anti-B antibodies

Type B Blood

Surface antigen B & anti-A antibodies

Type AB Blood

Surface antigens A & B & neither anti-A or anti-B antibodies

Type O Blood

Neither surface antigen A & B & both anti-A & anti-B antibodies

Rh+

Surface antigen D & no anti-D antibodies

Rh-

No surface antigen D & no anti-D antibodies unless exposed to Rh positive blood

Agglutination

Antibody in the recipient binds to the surface antigen of transfused erythrocytes leading to clumping of erythrocytes

Granulocytes

Contains secretory vesicles & includes neutrophil, basophil, & eosinophil

Agranulocytes

No cytoplasmic granules & includes lymphocytes & monocytes

Neutrophils

Targets bacteria

Lymphocytes

Target virus

Monocytes

Phagocytize bacteria, virus, & dead cells

Eosinophils

Destroy parasites

Basophils

Allergic response

Platelets

Derived from megakaryocytes, cell fragments no nucleus, & stops bleeding

Hemostasis

A sequence of responses to stop bleeding