Hormones that influence osteoblasts and maintain the matrix

pituitary gland, secretes

Growth hormone

Function of growth hormone

Controls bone growth

Growth, hormone triggers

Chondrocytes proliferation in epiphyseal plates resulting in increase length of long bones

Growth hormone also increases

Calcium retention, which enhances mineralization

Stimulates osteoblastic activity

Improve bone density

When growth hormone is absent

Abnormal development of long bones of the limbs resulting in pituitary dwarfism

Excess growth hormone before ossification of epiphyseal disk

Height exceeds 8 feet

In adults, excess hormonal causes a hands and feet to enlarge

Hi 8 feet it’s called

Pituitary gigantism

In adults excess growth hormone is called

Acromegaly hands, feets and jaw enlarge

Hormones uses in bones

Growth hormone

Thyroxine

What gland secretes thyroxine?

Thyroid glands

Thyroxine

Promotes osteoblastic activity on the synthesis of bone matrix

Thyroxine stimulates

Replacement of cartilage in at the disc of long bones with bone tissue.

Can halt bone growth by premature ossification of disc

Calcitriol

Stimulates absorption of calcium and phosphate from digestive system

Sex hormones estrogen in girls testosterone in boys

at puberty, promote osteoblastic activity, production of bone, matrix and responsible for growth spurt during adolescent.

Also promote the conversion of the epiphyseal plate to the epiphyseal line, and then longitudinal growth of bones

Why do females reach their maximum height earlier than males?

The effect of estrogen on the disc is stronger than antigens so female reach their maximum height earlier

Hormones that influence osteoclasts

1. Parathyroid hormone
2. Calcitonin

Parathyroid hormone

Stimulates, osteoclast, proliferation, and activity, and a release of calcium from bones into blood

Parathyroid hormone

Promotes the absorption of calcium by the kidney tubules

Parathyroid hormone

Simulate synthesist of vitamin D and indirectly increase calcium uptake by the small intestines

Calcitonin secreted by

thyroid gland

Calcitonin

Inhibits osteoclast activity and stimulate Calcium uptake by bones so reduces concentration of calcium into the blood

Mechanical, /Physical stress

Stimulate deposition of mineral salts and collagen, fibers, thickening, and strengthening bones hypertrophy

Lack of mechanical stress, or exercise

Bones lose mineral salts, and collagen fibers, waste and become thinner and weaker

Why are bones of athletes, stronger and heavier than non-athletes?

Due to exercise and mechanical stress

Wolffs’law

Bones adapt based on the stress or demands on them

Exercise on bones

Exercise stimulates the deposition of bone tissue

Resistance training

Important to slow down, eventual bone lose due to aging and for preventing osteoporosis

Osteoporosis

Decrease in Bone mass occurring when rate of bone resorption exceeds bone formation

How to test for osteoporosis?

Occurrence as a body age is therefore old people

More common in women than men, as women lose Bone mass more rapidly starting at age 50

Family history

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osteoporosis affect which area of the body

Femur

Vertebrae

Wrist

Osteogenesis imperfecta

Brittle bone disease

Brittle bone disease

Genetic disease bones do not form properly and our fragile and break easily

Which diseases is present from birth and affects a person throughout life

Osteogenesis imperfecta

Paget’s disease

Occurs in adults, 40 years and older more board is reabsorb that is laid down.

With Paget’s disease where is affected?

Bones of the pelvis

Skull

Spine

Legs