RESEPTOR & HORMON

BLOK ENDOKRIN28 Mei 2012

HORMON

• Molekul yang disintesis suatu sel sebagai media informasi yang mempengaruhi efek biologi sel itu sendiri, sel tetangga atau sel target yang letaknya jauh.

• Jukstakrin/contact depending signaling: caderin, molekul MHC,

• Parakrin : somatostatin• Autokrin : insulin, • Endokrin : TSH, LH, FSH

The Role of Insulin in the Human Body - YouTube.flv

• Apakah hormon hanya di hasilkan oleh organ endokrin?

• Apakah sitokin termasuk hormon?

Figure 15-4 Molecular Biology of the Cell (© Garland Science 2008)

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Cytotoxic T cell - YouTube.flv

Klasifikasi hormon

berdasar sifat kimia 1. turunan asam amino : tiroid, epineprin, norepineprin, serotonin2. polipeptida pendek,

oksitosin, ADH, MSH, ACTH3. protein dan glikoprotein, insulin, TSH, LH, FSH, PTH, prolaktin,

4. Steroid mineralkortikoid, glukokortikoid, estrogen, progesteron, androgen5. Eikosanoid, lipid prostaglandin, tromboksan

Berdasar asal organ• Kelenjar endokrin

– Hormon dari kelenjar hipofisis, adrenal, tiroid, dll• Non kelenjar endokrin

– Natriuretic peptida (jantung), – eritropoetin & renin (ginjal)– leptin dan adiponectin (jaringan lemak )– Kolesistokinin, gastrin (saluran pencernaan)

Berdasarkan sifat kerjanyaA. bekerja cepat > mengaktifkan enzim : Adrenalin, noradrenalin, ACTH, TSH,

LH, parathormon, vasopresin, glukagon

B. perkembangan & mempercepat pertumbuhan :hormon pertumbuhan, > sintesis protein /transkripsi gen

: hormon tiroid, hormon steroid kelamin (estrogen, progesteron, dan androgen)

Figure 15-6 Molecular Biology of the Cell (© Garland Science 2008)

Understanding Vitamin D - YouTube.flv

Efek cepat atau lambat?

• hormon gastrin dan histamin membuka chanel Cl sehingga keluar dari sel parietal

Berdasarkan mekanisme kerjanyaA. mengikat reseptor di dalam sel : hormon

tiroid (inti sel) & steroid (sitoplasma)B. mengikat reseptor pada permukaan sel :

hormon derivat asam amino, peptida & protein

Situation of the hormonal receptors

■ MECHANISM OF HORMONAL ACTION

On the target cell, the hormone in combination with the receptor act by any of the following mechanism.

1. By altering the permeability of the cell membrane. - Neurotransmitter substances. 2. By activating the intracellular enzyme. - Protein hormones and catecholamines 3. By activating the gene. - Thyroid and steroid hormones

Figure 15-1 Molecular Biology of the Cell (© Garland Science 2008)

Reaksi yg akan terjadi :• Mekanisme pengaktifan / penonaktifan protein

dengan cara :• Fosforilasi (Penambahan gugus fosfat) &

DefosforilasI (Pengurangan gugus fosfat) • Pengaktifan GTPase• Produksi SECOND MESSENGER

• Cyclic adenosine monophosphate (cAMP)• Cyclic guanosine monophosphate (cGMP)• Diacylglycerol (DAG)• Inositol 1,4,5-triphosphate (IP3)• Calcium

Figure 15-18 Molecular Biology of the Cell (© GarlandScience 2008) #16.

Figure 15-20 Molecular Biology of the Cell (© Garland Science 2008)

• Klasifikasi hormon Berdasar reseptor A.Permukaan sel

– Seven transmembran domain (reseptor terkait protein G)

• LH, TSH, GRH, ACTH, Glukagon, PTH, dopamin– Reseptor terkait protein tirosin kinase

• Insulin, IGF– Reseptor sitokin

• GH, eritropoetin, prolaktin– Reseptor terkait guanylyl cyclase

• Natriuretic peptida– Ion-channel-linked receptor

• neurotransmiter

B. Nuclear reseptor• Steroid reseptor family

– Glukokortikoid, mineralkortikoid, androgen, progesteron

• Thyroid reseptor family– Tiroid, estrogen, vitamin D

Figure 15-16b Molecular Biology of the Cell (© Garland Science 2008)

Reseptor terkait protein GLH, TSH, GRH, ACTH, Glukagon, PTH, dopamin, epinefrin

G-protein Coupled reseptor• stimulasi adenylyl cyclase – cAM• stimulasi PLC (phospholipase C)

Table 15-1 Molecular Biology of the Cell (© Garland Science 2008)

Figure 15-36 Molecular Biology of the Cell (© Garland Science 2008)

action of epinephrine - YouTube.flv

Table 15-2 Molecular Biology of the Cell (© Garland Science 2008)

Figure 15-39 Molecular Biology of the Cell (© Garland Science 2008)

Catalytic/Tyrosin Kinases /Growth Factor

Receptor

Insulin, IGF

Figure 15-16c Molecular Biology of the Cell (© Garland Science 2008)

Figure 15-53a Molecular Biology of the Cell (© Garland Science 2008)

Figure 15-53b Molecular Biology of the Cell (© Garland Science 2008)

Figure 15-60 Molecular Biology of the Cell (© Garland Science 2008)

GLUT-4 intracellular membrane vesicle exocytosis by Insulin Signaling - YouTube.flv

• Insulin berikatan dengan reseptor ini di banyak sel > sel membuat GluT4 (protein transport di bawa ke membran sel, sehingga glkukosa masuk ke dalam sel.

• Kalau di sel hepar Glut sudah terbentuk glukosa senantiasa dapat masuk ke sel hepar

Cytokine receptor

GH, eritropoetin, prolaktin

Figure 15-68 Molecular Biology of the Cell (© Garland Science 2008)

Table 15-6 Molecular Biology of the Cell (© Garland Science 2008)

• Natriuretic peptida > guanylyl cyclase > cGMP > PKG > ion channel

Ion Channel-Linked Receptors

INTRA SEL RECEPTOR

Situation of the hormonal receptors

Steroid reseptor family

• Jika tidak ada hormon reseptor ini terikat dengan protein HSP

• Ada hormon, HSP lepas

• R+HSP+DNA (HRE)

Chapter 47 Mechanism of Steroid Hormone Action 1 - YouTube.flv

Thyroid reseptor family

• Reseptor dimer• Reseptor jika tidak terikat hormon

berikatan dengan protein represor dan histon deasetilase

• Ada hormon reseptor terikat protein koaktivator dan histon asetilase > aktivasi transkripsi gen

•Gene regulation by the thyroid hormone receptor Thyroid hormone receptor binds DNA in either the presence or absence of hormone. However, hormone binding changes the function of the receptor from a repressor to an activator of target gene transcription.

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• Beberapa hormon steroid beraksi non genomic misalnya Ikatan Estrogen dan reseptornya

• ER ada di membran plasma