After that read the text aloud, trying to imitate the intonation. According to Hans Selye[1], the term “сatatoxic reactions” means active protection while the term “syntoxic reactions” is used to define passive protection

According to Hans Selye[1], the term “сatatoxic reactions” means active protection while the term “syntoxic reactions” is used to define passive protection. Catatoxic and syntoxic reactions are intermingled parts of any adaptive process.

The dependence of many protective reactions on central mechanisms integrating reactivity is not too strong. Being adaptive at the level of the cell, tissue and organ, they may be pathogenic at the level of the organism as a whole. Thus, the effects of the mediators of inflammation within the limits of the inflammed zone may be sanogenic; however, the effects of their massive penetration into the systemic circulation are pathogenic. Mechanisms of reactivity are only relatively beneficial and potentially pathogenic.

Ontogenesis is the process of asynchronous expression and repression of the unfolding genetic programs. That is why individuals of different ages have different reactivity. New born human beings, like vertebrate and invertebrate animals at early stages of their ontogenesis, are more resistant to acute hypoxia (Sirotinin’s[2] rule), since:

1) isoenzymes of PhFK (phosphofructokynase) are insensitive to increased levels of lactate acidosis;

2) the amount of fetal Hb in blood circulation is much greater;

3) the absolute basal metabolic rate (BMR) is markedly lower;

4) there are certain peculiarities in the catecholamine status and the amount of receptors of catecholamines on cardiomyocytes, such as:

a) secretion of catecholamines by the adrenal medulla cells occur in response to hypoxia in secretory cells;

b) epinephrine/nor-epinephrine ratios in adrenal medulla secretions are 1:1; compared to predominance of epinephrine in adults. Nor-epinephrine effectively increases surfactant secretion in lungs. It is also significant for cold adaptation of neonates via urgent lipolysis in brown fat.

c) the number of epinephrine receptors in cardiomyocytes is not sufficient for induction of tachycardia. Bradycardia is more effective response for hypoxia for fetal conditions. All this is also true for anti-hypoxial mechanisms of diving animals, like seal or cachalot.

3 Do the following statements agree with the information given in the text?

Write

TRUE if the statement agrees with the information

FALSE if the statement contradicts the information

1. The term “сatatoxic reactions” is used to define passive protection while the term “syntoxic reactions” is used to define active protection.

2. Сatatoxic and syntoxic reactions are parts of any adaptive process.

3. The dependence of many protective reactions on central mechanisms integrating reactivity is very strong.

4. The effects of the mediators of inflammation within the limits of the inflammation zone may be pathogenic; however, the effects of their penetration into the circulation are sanogenic.

5. Mechanisms of reactivity are only relatively beneficial and potentially pathogenic.

6. Ontogenesis is the process of asynchronous repression and expression of the unfolding genetic programmes.

7. Individuals of different ages have different reactivity.

8. New born human beings, unlike vertebrate and invertebrate animals at early stages of their ontogenesis, are more resistant to acute hypoxia.

4 9 Listen to the following questions and repeat them. Mind the intonation in general and special questions. Then answer the questions and practice them with your partner.

1. Is the term “catatoxic reaction” used to define passive protection?

2. What does the term “сatatoxic reactions” express?

3.Parts of what process are catatoxic and syntoxic reactions?

4. How strong is the dependence of protective reactions on central mechanisms integrating reactivity?

5.. How may the mechanisms of reactivity be characterized in terms of usefulness?

6. What is ontogenesis?

7. Why are new born human beings more resistant to acute hypoxia then adults?

8. Who was Nicolay Sirotinin and what is his contribution into ontogenetic aspects of reactivity doctrine?

9. Who was Hans Selye and what is his contribution into reactivity doctrine?

5 9 Match the words and expressions in column A with the words and expressions in column B. Then listen, check and repeat.

A	B
сatatoxic and syntoxic	of reactivity
active	hypoxia
adaptive	human beings
the level	cells
within the limits	metabolic rate
mechanisms	reactions
unfolding	receptors
new born	process
acute	protection
basal	of the inflammation zone
adrenal medulla	of the cell, tissue and organ
epinephrine	genetic programmes